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Part Numbers:
- 7015190 - (1995-1999) 8 Port High Boost
- 7015200 - (2000-2004) 4 Port High Boost
Kit Includes:
- (1) Supercharger Assembly
- (1) Idler Pulley Assembly
- (1) Drive Belt
- (1) Fitting Instructions
- (1) Support Bracket Assembly
- (1) Hose Kits
Optional Supercharger Pulleys (Not Included):
- Part #1016158 - 58 mm 10 PSI pulley
- Part #1016160 - 60 mm 8 PSI pulley
- Part #1016162 - 62 mm 7 PSI pulley
- Part #1016165 - 65 mm 6 PSI pulley
- Part #1016168 - 68 mm 5 PSI pulley
- Part #101617 - NN 14QVMMFZ
Tools Needed:
- Basic Mechanics tools
- Metric Sockets, Allen & Open-End Wrench Sets
- Masking Tape for Labeling Hardware and Parts
- Electrical Tape
- Clean Work Bench
- Parts Tray
- Rags or Shop Towels
- Teflon Tape
- Red Loctite
- Safety Goggles
- Toyota Repair Manual
Accessories (Not included in this kit):
- Boost gauge (recommended)
- Spark plugs
- AFR Gauge
- Header, High flow Cat, Cat back Exhaust System
Installation Preparation:
1. Before you begin, we recommend that you thoroughly clean the engine and engine compartment. If you
don't, grease buildup on parts could become dislodged during the procedure and fall into the engine.
2. Make sure the engine has cooled fully before beginning this installation.
3. To help you later, draw a diagram of your engine's vacuum hose routing before you disconnect anything. However, some of the vacuum connections on your intake manifold may not be the same as those on the supercharger. Study and closely follow the vacuum diagrams for your specific application included in the back pages of these instructions.
4. The LC Engineering supercharger kit has been designed to reuse most of the stock nuts and bolts. Therefore, as you remove them, keep them with their components or label them for location. This will assure a faster, easier installation.
Installation Instructions:
1. Disconnect the ground cable from the battery, and then the positive cable. Remove battery from the vehicle.
2. Remove air cleaner hose with resonator. ( See Figure 1)
3. Remove evaporation canister vacuum switch valve (VSV) hose.
4. Remove PCV hose.
5. Remove EGR modulator and hoses.
NOTE: Take note of hose location and routing for re-installation. (Figure 2)
6. Disconnect power steering idle-up connector from the sensor and also the wiring from the intake manifold bracket. (See arrows in Figure 3)
7. Remove fuel pressure regulator hose from intake air connector.
8. Remove intake air connector. (Figure 4)
9.Disconnect Throttle Position Sensor (TPS) connector from TPS in throttle body.
10. Disconnect Idle Air Control (IAC) connector from IAC in throttle body. Disconnect coolant line from IAC. Pinch off coolant lines before EGR valve.
11. If vehicle is equipped with EGR, then disconnect EGR connector from EGR sensor in intake
chamber.
NOTE: If no EGR go to step 15.
12. Remove throttle body from intake manifold and set aside. (Figure 5)
13. Disconnect EGR feed tube at EGR valve. See "A" arrows in (Figure 6).
14. Disconnect EGR valve from intake chamber.
15. Remove wire harness bracket from backside of intake chamber. See arrow "B" in (Figure 6.) Remove bracket from wire harness.
16. Remove bolt from the upper side of the intake chamber bracket see arrow in (Figure 7). Loosen lower bolt from air intake chamber bracket.
17. Disconnect the DLC 1 from the bracket on the air intake chamber assembly.
NOTE: 1995-2001 vehicles only.
18. Remove the wire harness bracket for the DLC 1 wiring from the air intake chamber assembly. 1995-2001 vehicles only.
19. Disconnect the brake booster vacuum hose from the intake chamber hose barb.
20. If your vehicle is equipped with EGR, then disconnect EGR tube bracket from the backside of the cylinder head.
21. Remove the 3 bolts and 2 nuts shown in (Figure 8).
22. Remove the air intake chamber and gasket. On vehicles with EGR.
23. Remove the injector wiring ground strap from the intake manifold.
24. Remove the 2 bolts from the fuel return pipe and disconnect the fuel return hose from fuel pressure regulator. See (Figure 9). Caution: Plug fuel return hose so that no fuel will spill. Set
pipe and hose aside.
25. Remove fuel pressure regulator from the fuel rail.
26. Disconnect wire loom clips from the intake manifold brackets and remove the clips from the wire loom. See arrows in (Figure 10).
27. On vehicles with EGR, remove the EGR vacuum switch valve bracket from the intake manifold.
28. Disconnect the camshaft position sensor connector. If equipped See (Figure 10).
29. Remove wire-loom bracket and clips from the
wire loom that was disconnected in Step 15.
30. Disconnect the detonation sensor connector (A), and the crankshaft position sensor connector (B). See (Figure 11). Both connectors are located next to the engine block, and below
the intake manifold.
31. Disconnect all four fuel injection connectors and set wiring aside.
32. On vehicles with EGR, remove the EGR coolant hose. Remove only the hose that runs down through the intake manifold runners. Plug hose so that coolant will not leak.
33. Disconnect the fuel inlet banjo fitting from the fuel rail. Remove both banjo washers.
See (Figure 12).
34. Remove the intake manifold from the cylinder head. You will replace the gasket with the new one in the kit.
35. Remove the original equipment (OE) intake manifold chamber stay.
36. Remove the evaporative canister steel line that is secured to the top of the radiator fan shroud and set aside.
37. On 2000 and earlier model years, step 36 may not be necessary. Check the power steering pressure feed hose clearance to the supercharger by installing the supercharger main assembly onto the cylinder head. When installing the supercharger, the supercharger drive pulley and snout slides under the power steering pump return hose. If necessary, adjust the power steering line next to the banjo fitting on the power steering pump. See (Figure 13). The steel line needs to be parallel
with the engine centerline.
NOTE: Adjust carefully so the steel line will not kink. When adjusted correctly, the rubber hose that is connected to the steel line will have clearance to the supercharger housing and also to the lower radiator hose check and remove.
38. Attach the new supplied 2-piece lower manifold bracket to the engine mount with one 8mm x 25mm long flange head hex bolt See arrow in (Figure 14). Make sure the L-portion of the bracket is towards the front of the vehicle. (Figure 14) shows the chamber stay in the assembled position. Attach only the lower bolt in this step. Tighten bolt finger tight.
39. Remove the radiator fan shroud for easier access to the components in the following steps. See (Figure 15).
40. Remove power steering belt. See (Figure 16).
41. Remove the two bolts that secure the power
steering pump to the pump bracket. See (Figure 18).
power steering pulley dose not have to be removed access
to the bolts is provided though the pulley holes.
42. Install the supplied idler pulley bracket to the front of the power steering pump. See (Figure
19).
NOTE: Pulley is removed for photos only. Use (2) 10mm x 1.25 x 100mm long bolts supplied. Both bolts replace the OE bolts removed in Step 40. Torque bolts to 29 ft-lbs.
NOTE: The idler pulley for the 3RZ should use
the top hole. The 2RZ uses the lower hole.
43. If your vehicle has eight round intake ports in the cylinder head, then proceed with steps 43
and 44.
NOTE: If your vehicle has four oval intake ports, then skip ahead to step 45.
44. The wires that connect to both the detonation sensor and the crankshaft position sensor need to be routed below the intake manifold. Remove the nylon split flexible tubing around the area where the wires join the main engine wire loom. See (Figure 23). Separate the detonation sensor and crankshaft position sensor wires back about 6" to 8" from the original breakout point. Use electrical tape to wrap the wires that have been split out from the main wire loom. Re-install the nylon split tubing around the main wire loom. Use electrical tape to secure the flexible tubing.
45. Connect the detonation sensor and crankshaft position sensor connectors before installing the supercharger.
Supercharger Installation:
46. When installing the supercharger, the supercharger drive pulley and snout slides under the power steering pump return hose. See (Figure 24). Before sliding the supercharger manifold over the attachment studs, insert the fuel line banjo fitting through the manifold between intake ports three and four. It is easiest to do this as the manifold is being lowered into place after the supercharger snout is in position. Use another person if necessary to help with the fuel inlet banjo fitting. Snug all the nuts and bolts to secure the supercharger to the cylinder head. Start in the center of the manifold and work outward towards the ends. Torque fasteners to 22 ft-lbs.
47. Rotate the supercharger nose support bracket to align the slot in the bracket with the idler bracket bolt hole. See (Figure 24). Use the supplied 10mm x 1.25 x 25mm long hex bolt and 10mm washer to secure the nose support bracket to the idler bracket. Finger tighten bolt.
48. Using the 8mm flange head nut supplied, secure the upper portion of the manifold support to the 8mm stud that is in the bottom-side of the intake manifold. The stud should protrude through the slot in the manifold support bracket. See Figure 25. Tighten bracket to supercharger first, and then also tighten to the engine mount. Torque: 15 ft-lbs. Finally, torque the manifold bracket 8mm through bolt and nylock nut to15 ft-lbs.
49. Tighten the 10mm bolt that secures the nose support bracket to the idler pulley bracket. Torque to 30 ft-lbs.
50. Tighten the socket head cap screw to secure the nose support bracket to the supercharger nose. Torque to 10 ft-lbs.
51. Check both the power steering pressure hose and return hose for clearance to the supercharger snout. Both lines should not touch the supercharger. Adjust lines as necessary.
52. Reconnect the fuel inlet banjo fitting to fuel rail. Torque to 22 ft-lbs.
53. Reconnect all four fuel injection connectors.
54. Attach injector wiring ground strap removed in Step 23 to the supercharger intake manifold using the supplied 6mm hex bolt and washer. Clean wires and and the connection location before installing. See (Figure 26). Torque to 6 ft-lbs NOTE: If your vehicle has eight round intake manifold ports, then skip to step 64. If your vehicle has four oval ports, then follow steps 62 and 63.
55. Route the crankshaft position sensor connector down through the opening between the intake port one and intake port two of the supercharger manifold and connect to the crankshaft position sensor.
56. Route detonation sensor connector through the intake manifold between ports two and three, and then connect to the detonation sensor.
57. Reconnect power steering idle up connector. Install the OE wiring bracket on to the super charger stud. Torque nylock nut to 15 ft-lbs. See (Figure 27).
58. On vehicles with EGR, remove the EGR temperature sensor (Arrow A) and EGR modulator bracket (Arrow B) from the OE intake chamber. See (Figure 28).
59. Check the OE intake chamber that was removed from the vehicle. Look at the quantity and location of the PCV breather fitting that are next to the throttle body surface. See
(Figure 29).
60. Check the intake chamber to make sure that the quantity and location of the PCV / breather
fittings match the OE intake chamber. See (Figure 30).
NOTE: The intake chamber is photographed off the engine for clarity. If the fittings match, then proceed with Step 68. If the fittings do not match, then use the supplied fittings to duplicate the previous /breather fittings in the OE intake chamber. Re-use the 16mm nylon washers to seal the fittings into the intake chamber.
61. If vehicle has EGR, install the EGR temperature sensor (Arrow A) to the intake chamber.
See (Figure 30). Otherwise, install the supplied 10mm x 1.25 x 12mm long bolt. Teflon thread
tape is recommended.
62. If vehicle has EGR then proceed with Steps 62 through 75, If vehicle has no EGR, then skip to Step 68.
63. Use one of the supplied EGR gaskets and install the EGR valve to the backside of the intake chamber. See (Figure 31). Use the OE EGR valve nuts removed in Step 14. Leave the nuts loose at this time.
64. Use the second supplied EGR gasket and connect the EGR feed tube to the EGR valve. Again, use the OE nuts removed in Step 13. Leave nuts loose at this time.
65. Torque EGR valve nuts to 14 ft-lbs.
66. Install EGR feed tube. Torque to 14 ft-lbs
67. Reconnect EGR coolant hose removed in Step 31.
68. Re-install the EGR modulator bracket to the backside of the intake manifold using the OE bolt removed in Step 65. Refer to (Figure 31)
69. If the vehicle has no EGR, then use one EGR gasket, block-off plate, and two 8 x 1.25mm flange nuts to seal the EGR passage located on the backside of the intake chamber.
See (Figure 32). Torque nuts to 14 ft-lbs
70. Position supplied throttle body gasket on to the studs on the intake chamber. Position the OE throttle body also on the studs.
71. Reconnect TPS and lAC connectors to the sensors in the throttle body also reinstall coolant lines.
72. Reconnect cam position sensor connector removed in Step 27.
73. Tighten the OE nuts and bolts to secure the throttle body to the intake chamber.
Torque to 14 ft-lbs
74. Reconnect the brake booster vacuum hose to the hose fitting on the side of the intake chamber. Cut hose if needed. See (Figure 33) Arrow "A"
75. Remove the OE fuel return pipe and hose. Disconnect the OE hose at the hard line that is mounted on the inner fender panel. Install the new supplied fuel return hose using the OE clamps removed in Step 24. Route the new hose under the supercharger. Hook up new line at the frame rail.
76. Remove the OE fuel return pipe and hose.
Disconnect the OE hose at the hard line
that is mounted on the inner fender panel.
Install the new supplied fuel return hose using
the OE clamps removed in Step 24. Route the
new hose under the supercharger. Hook up
new line at the frame rail.
77. Install the supplied fuel block under the stock fuel pressure regulator. Route the 5th injector fuel line towards the fire wall use supplied del clamps to mount.
78. Install supercharger drive belt using the supplied drive belt routing label as a guide. Find a suitable area under the hood to mount the drive belt routing label. Clean area to remove any dirt or grease and affix label.
79. Re-install the radiator fan shroud removed in Step 38.
80. Re-install the steel line that was removed from the fan shroud in Step 35.
81. Remove the valve cover bolt and sealing washer from the rear hole on the driver side of the valve cover. See (Figure 34). Remove the sealing washer from the bolt. Use the earn cover bolt to mount the supplied "Z" bracket onto the earn cover. The bracket should sit on top of the sealing washer. Tighten cam cover bolt.
82. Mount the EGR modulator VSV to the "Z" bracket. See (Figure 35). Use the OE 6mm bolt and washer removed in Step 26. Torque bolt to 6 ft-lbs.
83. Reconnect the VSV hoses and EGR modulator hoses per the vacuum diagram on the under side of the vehicle hood.
84. Reconnect the PCV hose from the PCV valve to the PCV fitting on the intake manifold. See (Figure 36) Arrow “A”
85. Reconnect the valve cover breather hose to the fitting on the throttle body. See (Figure 36) Arrow "B".
86. Re-install intake air connector onto throttle body. See (Figure 37). Secure intake air connector-to-connector bracket using two OE nuts removed in Step 2. Torque nuts to 13 ft-lbs.
87. Re-install air cleaner hose with resonator.
88. On 1995-2001 vehicles, follow Steps 95 and 96. Mount OE DLC 1 bracket to the unused boss on the cylinder head. See (Figure 38). Use the OE bolt removed in Step 18. Torque bolts to 6 ft-lbs.
89. Slide the DLC onto the bracket until it locks into place .
90. Install the supplied 1/8" NPT barb fitting into the manifold using thread sealant on the threads. Connect to the power steering vacuum line (See Fig. 39). On kits with the fifth injector install the tee fitting and run vacuum line through the firewall so it may connect to the split second box.
91. Reconnect the fuel regulator hose.
92. Re check all vacuum lines for proper placement and connection.
93.
NOTE: The use of this kit requires the use of Premium high octane fuel only Min. 92.
94. In States that require smog checks apply the EO decal to the underside of the hood. This will alert smog inspectors that the kit is 50 state legal
95. On vehicles that do not need the 1/4” vacuum hose fitting that is installed on the front of the throttle body manifold use a rubber cap to block
it off. See (Figure 40).
96. Use cable ties to secure all wiring and vacuum line as necessary.
97. Re-install battery cable.
98. Start Engine and check for vacuum and air leaks. Diagnose and repair any problems found.
On vehicles that are running low boost kits, the computer will make adjustments for the increase in air to the engine. Please know that the vehicles will not run properly until the computer makes the necessary adjustments. It will take around two tanks of gas or several hundred miles (approx). Our High Boost Kits will Require the install of the FTC Split Second piggy back fuel and timing controller. See instructions below of this for the
High Boost Controller install instructions.
NOTE: In order to reach optimum performance the
vehicle must be driven several hundred miles. Usually
two tanks of fuel. This will allow the ECU to fully adjust
to the additional air flow. Premium fuel is required
to be used.
Installation of the FTC Split Second controller:
1. The Battery must be disconnected during the install of the FTC.
2. The Tacoma ECU is installed behind the glove box. Remove glove box door and lower finish panel to gain access to the ECU wiring harness.
Location of ECM on Tacomas
3. All connections to the ECU should be of solder and shrink wrap for the best possible connection. Keep all connections at least 2” away from the ECU. Cut wires at least 2” away from ECU.
4. Hook up vacuum line that was brought in from step 89 (on the supercharger install instructions).
5. Follow the ECU wire Diagram for your plug configuration. If you do not see the proper
ECU plug pin out, call LC Engineerings Tech Support. (928) 855-6341. Please make sure you have your VIN in hand.
Use and Installation Instructions For the FTC Controller:
- Tuning can be done using the R4 software included on cd but not required.
- Disconnect the battery before making connections to the factory wiring harness.
- The following wires will need to be hooked up to the stock ECU. See diagrams in the following pages.
- Use solder and heat shrink for the best possible electrical connections. NOTE: Do not use quick connectors.
The following instructions are for loading programs to the controller. These units come already programmed by LC Engineering for 4 Cylinder Tacoma's. Instructions provided just in case the controller needs to be re-programmed in the future.
1. Use with R4 software.
2. Select Vac/Pressure and Additional Injector Controller under system settings. Refer to the AIC1 and FTC1 data sheets for more information.
3. Select 2-cylinder, 2-stroke under Engine Settings.
4. Program timing retard in Map table A.
5. The cell values can range from 0 to 20. A value of 20 will result in 20 degrees of retard. (Cell values can have one decimal place. For example 10.1. There are a total of 200 levels available for cell value).
6. Program the fuel in Map table B.
7. The cell value represents the additional injector on-time in milliseconds. The minimum practical cell value is 1.0 the maximum call value will have a corresponding duty cycle of 40%.
8. The highest cell value is 25.5, but you should never get anywhere near that number. (Cell values can have one decimal place. For example 10.1. There are a total of 200 levels available for cell value).
9. Program the enrichment threshold and optional relay activation through the output B mode selection. Typical settings are for Over Pressure and a threshold of 1 psi.
10. Make sure the vacuum line is connected to the FTC controller from the intake manifold.
11. Reconnect the battery
NOTE: Advanced Option Not Required:
Orange wire is not used in this set up If you would like to control an external load with the R4 software
connect the ORANGE wire as follows.. Connect the ORANGE relay driver wire to the negative side of the
relay coil Connect the coil positive to a fused B+ circuit Switch the load through the relay contacts, Set up the
turn-on threshold for the relay under options, output settings and output B The threshold can be set according
to any combination of RPM and pressure set points. If Using the advanced tunning options you will need a windows computer and serial cable for connections to
the FTC controller. The R4 software will need to be installed if you want to use the advanced options and tune
the FTC see the included R4 instructions and CD Rom.
FTC1-115D Fuel/Timing Calibrator for 2.4L Toyota 2RZ
Use and Installation Instructions (ECU referenced to 1995.5 thru 1997 2RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-12.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E8-14.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-3.
7. Cut the RED (crank sensor) wire leading to ECU pin E8-4.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E8-5.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Cut the WHITE (OX1) wire leading to ECU pin E7-6.
14. Connect the PINK wire to the cut wire leading to the sensor.
15. Connect the PINK/BLUE wire to the cut wire leading to the OX1 ECU input.
16. Cut the BLACK (OX2) wire leading to ECU pin E7-5.
17. Connect the WHITE wire to the cut wire leading to the sensor.
18. Connect the WHITE/GREEN wire to the cut wire leading to the OX2 ECU input.
19. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
20. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.7L Toyota 3RZ
Use and Installation Inst (ECU referenced to 1995.5 and 1996 3RZ-FE Tacoma with MT):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-12.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E8-13.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-3.
7. Cut the RED (crank sensor) wire leading to ECU pin E8-4.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E8-5.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Cut the WHITE (OX1) wire leading to ECU pin E7-6.
14. Connect the PINK wire to the cut wire leading to the sensor.
15. Connect the PINK/BLUE wire to the cut wire leading to the OX1 ECU input.
16. Cut the BLACK (OX2) wire leading to ECU pin E7-5.
17. Connect the WHITE wire to the cut wire leading to the sensor.
18. Connect the WHITE/GREEN wire to the cut wire leading to the OX2 ECU input.
19. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
20. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.7L Toyota 3RZ
Use and Installation Inst (ECU referenced to 1995.5 and 1996 3RZ-FE Tacoma with AT):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-12.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E8-13.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-17.
7. Cut the RED (crank sensor) wire leading to ECU pin E6-12.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E6-11.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Cut the WHITE (OX1) wire leading to ECU pin E7-5.
14. Connect the PINK wire to the cut wire leading to the sensor.
15. Connect the PINK/BLUE wire to the cut wire leading to the OX1 ECU input.
16. Cut the BLACK (OX2) wire leading to ECU pin E7-13.
17. Connect the WHITE wire to the cut wire leading to the sensor.
18. Connect the WHITE/GREEN wire to the cut wire leading to the OX2 ECU input.
19. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
20. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.4L Toyota 2RZ
Use and Installation Instructions (ECU referenced to 1998 and 1999 2RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-12.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E8-24.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-17.
7. Cut the RED (crank sensor) wire leading to ECU pin E6-12.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E6-11.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Cut the WHITE (OX1) wire leading to ECU pin E7-5.
14. Connect the PINK wire to the cut wire leading to the sensor.
15. Connect the PINK/BLUE wire to the cut wire leading to the OX1 ECU input.
16. Cut the BLACK (OX2) wire leading to ECU pin E7-13.
17. Connect the WHITE wire to the cut wire leading to the sensor.
18. Connect the WHITE/GREEN wire to the cut wire leading to the OX2 ECU input.
19. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
20. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.7L Toyota 3RZ
Use and Installation Inst (ECU referenced to 1997 thru 1999 3RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-12.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E8-13.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-17.
7. Cut the RED (crank sensor) wire leading to ECU pin E6-12.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E6-11.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Cut the WHITE (OX1) wire leading to ECU pin E7-5.
14. Connect the PINK wire to the cut wire leading to the sensor.
15. Connect the PINK/BLUE wire to the cut wire leading to the OX1 ECU input.
16. Cut the BLACK (OX2) wire leading to ECU pin E7-13.
17. Connect the WHITE wire to the cut wire leading to the sensor.
18. Connect the WHITE/GREEN wire to the cut wire leading to the OX2 ECU input.
19. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
20. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.4L Toyota 2RZ
Use and Installation Instructions (ECU referenced to 2000 California 2RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-16.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E7-17.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-10.
7. Cut the RED (crank sensor) wire leading to ECU pin E7-16.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E7-15.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Connect the PINK/BLUE wire to the WHITE wire on ECU pin E7-11.
14. The PINK wire is not used and can be left disconnected.
15. Cut the BLACK (OXS) wire leading to ECU pin E7-10.
16. Connect the WHITE wire to the cut wire leading to the sensor.
17. Connect the WHITE/GREEN wire to the cut wire leading to the OX1 ECU input.
18. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
19. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.7L Toyota 3RZ
Use and Installation Instructions (ECU referenced to 2000 CA 3RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-16.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E7-17.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-10.
7. Cut the RED (crank sensor) wire leading to ECU pin E7-16.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E7-15.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Connect the PINK/BLUE wire to the WHITE wire on ECU pin E7-11.
14. The PINK wire is not used and can be left disconnected.
15. Cut the BLACK (OXS) wire leading to ECU pin E7-10.
16. Connect the WHITE wire to the cut wire leading to the sensor.
17. Connect the WHITE/GREEN wire to the cut wire leading to the OX1 ECU input.
18. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
19. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.4L Toyota 2RZ
Use and Installation Instructions (ECU referenced to 2000 Non-CA 2RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-12.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E8-24.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-17.
7. Cut the RED (crank sensor) wire leading to ECU pin E6-12.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E6-11.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Cut the WHITE (OX1) wire leading to ECU pin E7-5.
14. Connect the PINK wire to the cut wire leading to the sensor.
15. Connect the PINK/BLUE wire to the cut wire leading to the OX1 ECU input.
16. Cut the BLACK (OX2) wire leading to ECU pin E7-13.
17. Connect the WHITE wire to the cut wire leading to the sensor.
18. Connect the WHITE/GREEN wire to the cut wire leading to the OX2 ECU input.
19. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
20. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.7L Toyota 3RZ
Use and Installation Instructions (ECU Referenced to 2000 Non-CA 3RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-12.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E8-13.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-17.
7. Cut the RED (crank sensor) wire leading to ECU pin E6-12.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the YELLOW (cam sensor) wire leading to ECU pin E6-11.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Cut the WHITE (OX1) wire leading to ECU pin E7-5.
14. Connect the PINK wire to the cut wire leading to the sensor.
15. Connect the PINK/BLUE wire to the cut wire leading to the OX1 ECU input.
16. Cut the BLACK (OX2) wire leading to ECU pin E7-13.
17. Connect the WHITE wire to the cut wire leading to the sensor.
18. Connect the WHITE/GREEN wire to the cut wire leading to the OX2 ECU input.
19. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
20. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.4L Toyota 2RZ
Use and Installation Inst (ECU referenced to 2001 thru 2004 2RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-16.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E7-17.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-10.
7. Cut the RED (crank sensor) wire leading to ECU pin E7-15.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Connect the BLUE wire to the cut wire leading to the cam sensor.
11. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
12. Cut the WHITE (OX1) wire leading to ECU pin E7-5.
13. The PINK wire is not used and can be left disconnected.
14. Connect the PINK/BLUE wire to the VIOLET wire on ECU pin E7-11.
15. Cut the BLACK (OXS) wire leading to ECU pin E7-10.
16. Connect the WHITE wire to the cut wire leading to the sensor.
17. Connect the WHITE/GREEN wire to the cut wire leading to the OXS ECU input.
18. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
19. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
FTC1-115D Fuel/Timing Calibrator for 2.7L Toyota 3RZ
Use and Installation Instructions (ECU referenced to 2001 thru 2004 3RZ-FE Tacoma):
1. Disconnect the battery before making connections to the factory wiring harness.
2. Use solder and heat shrink for the best possible electrical connections.
3. The following wires are in the main wire group.
4. Connect the RED wire (B+) to the WHITE/RED wire on ECU pin E5-16.
5. Connect the BLACK wire (B-) to the BROWN wire on ECU pin E7-17.
6. Connect the BLACK/YELLOW wire (tach) to the BLACK/YELLOW wire on ECU pin E8-10.
7. Cut the BLUE (crank sensor) wire leading to ECU pin E7-16.
8. Connect the GREEN wire to the cut wire leading to the crank sensor.
9. Connect the GREEN/RED wire to the cut wire leading to the ECU crank sensor input.
10. Cut the RED (cam sensor) wire leading to ECU pin E7-15.
11. Connect the BLUE wire to the cut wire leading to the cam sensor.
12. Connect the BLUE/WHITE wire to the cut wire leading to the ECU cam sensor input.
13. Connect the PINK/BLUE wire to the VIOLET (AF+) wire on ECU pin E7-11.
14. The PINK wire is not used and can be left disconnected.
15. Cut the BLACK (OXS) wire leading to ECU pin E7-10.
16. Connect the WHITE wire to the cut wire leading to the O2 sensor
17. Connect the WHITE/GREEN wire to the cut wire leading to the ECU O2 input.
18. Connect the RED and TAN wires in the small wire group to the corresponding wires
on the injector harness.
19. Reconnect the battery.
Optional: If you would like to control an external load with the R4 software connect the
ORANGE wire as follows.
1. Disconnect the battery before making connections to the factory wiring harness.
2. Connect the ORANGE relay driver wire to the negative side of the relay coil.
3. Connect the coil positive to a fused B+ circuit.
4. Switch the load through the relay contacts.
5. Set up the turn-on threshold for the relay under options, output settings and output B.
6. The threshold can be set according to any combination of RPM and pressure set
points.
7. Connect the vacuum line to intake manifold vacuum.
8. Reconnect the battery.
Trouble Shooting
Split Second Piggyback Tuning
Piggyback tuning is the process of adjusting the operation of a stock engine management system to make a modified engine run properly. Piggyback tuning involves some type of hardware that is used in addition (piggyback) to the stock Electronic Control Unit (ECU). The other widely used methods for tuning modified engines are ECU reprogramming and stand-alone engine tuning where the stock ECU is replaced with an aftermarket unit.
ECU reprogramming is a very effective way to tune an engine. It involves changing map tables and control registers to directly adjust ECU operation and the tune of the engine. Reprogramming has the advantage that it does not require any additional hardware and does not alter any wiring. Reprogramming is well suited for stock engines or engines with well defined modifications. It is not always an option. In many cases a reprogramming solution is not available, or undesirable due to warranty concerns. Most manufacturers will void the powertrain warranty if the ECU has been reprogrammed. A common problem with late model vehicles is that dealerships frequently reprogram vehicles when they come in for service as new versions of ECU software are released. When this happens, the aftermarket tune is lost.
Stand-alone systems offer the highest level of flexibility and versatility. This comes at a relatively high cost. Stand-alone ECUs are expensive. There is also considerable additional cost in sensors, wire harness and tuning. Stand-alone tuning is generally used in off-road and racing applications. Modern street cars have too many interconnected modules to make a stand-alone ECU practical. Stand-alone ECUs lack support for the OBDII diagnostic port and do not meet emission requirements for operation on public roads.
What Piggyback Tuning Can Do:
There are many cases where piggyback tuning is the best solution. Piggyback tuning can be used to change ECU inputs and outputs to achieve the desired results. Mass air flow (MAF) sensor signals can be changed to adjust fuel mixture and compensate for larger injectors. Crank and cam sensor signals can be delayed to retard timing in boost as needed to avoid detonation. Manifold Absolute Pressure (MAP) sensor signals can be clamped to avoid fuel cut on supercharged and turbocharged engines. The injector pulse-width can be changed to add or take away fuel. This short list gives just a taste of what can be done.
Piggyback tuning can be used on stock engines to optimize performance. In many cases, manufacturers run a very rich fuel mixture at wide open throttle and higher RPM. One of the reasons for doing this is to cool the cylinder temperature and prolong engine and catalytic converter life. Often the mixture is so rich that a gain of ten horsepower can be realized by just leaning out the mixture to a normal optimum 12.5:1 Air Fuel Ratio (AFR).
Piggyback tuning has application on engines with mild modifications like a cold air intake, free- flowing exhaust and lightweight flywheel. In many cases these modifications are unique to an individual vehicle. Unique modifications don’t lend themselves to a one-size-fits-all chip tune or re-flash. A programmable piggyback calibrator can be a very effective way to get the most out of mild engine modifications.
Piggyback tuning can be very effective in tuning aftermarket turbo and supercharger applications. Piggyback methods are widely used to compensate for larger injectors, keep signals within their normal range, retard timing as needed and adjust for the correct AFR in boost. Applications with boost up to 14 psi and even higher can be served effectively using piggyback techniques.
Load sensor calibration can be used to make larger injectors work that are as big as double the size of stock injectors. For even higher fuel requirements, piggyback controllers can be used to control additional injectors. High boost, high horsepower engines can be fueled with an additional injector per cylinder.
What Piggyback Tuning Can’t Do:
There are things that piggyback tuning can do and things that it can’t. The essential limitation is that you are constrained by working within the limitations of the stock engine management system. For example, if the ECU is in closed loop and you try to change the fuel mixture, the ECU will do everything it can to restore its target mixture. This in turn can be overcome by altering the O2 sensor feedback to the ECU. Changes to the O2 sensor readings must be done in a way that readings stay within their normal range and continue to respond to fuel mixture changes.
The main limitation when adjusting sensor signals is to keep them within their normal range. For example it is common for a MAP sensor to have a maximum reading of 4.6 V. ECU programming is often set to generate a fault if the reading is greater than 4.7 V. That means that when you reach 4.6 V on a MAP sensor signal, it’s game over. You can’t add fuel at that point by simply increasing the reading. In fact you are more likely to induce fuel cut.
Beyond keeping signals within their normal operating range, you must keep signals within their range of plausibility. ECUs are programmed to expect a range of readings from an MAF sensor given a certain TPS reading. If the MAF sensor deviates outside the expected value range, the ECU will set a fault. This means you can’t just do whatever you want when doing piggyback tuning. You have to operate within the limits that the ECU gives you.
The Engine Management System:
Figure 1 shows a basic block diagram of the engine management system. The ECU operates as an integral part of the entire system. It takes in inputs from sensors that provide critical information about the engine such as coolant temperature, air temperature, barometric pressure, throttle position, air flow and crank position. These inputs determine the current operating conditions. Based on these conditions and the programmed response, the ECU generates the appropriate outputs to various actuators. The ignition coils, fuel injectors, idle air valve and other assorted solenoids and switches control the physical processes in the engine.
Piggyback calibration can be used on either the inputs or outputs of the ECU. For example, the MAF sensor signal input can be adjusted to change injector pulse-width. Fuel can also be adjusted by intercepting the injector drive signals and changing the pulse-width directly. There are pros and cons to each approach. Adjusting the MAF can be accomplished by intercepting a single signal versus multiple signals for each injector. On the other hand, intercepting the injector drive signals provides direct control while changing the MAF reading is a more indirect method that is limited by ECU programming.
Piggyback Signal Calibration:
The reading from the primary load sensor can be modified in order to achieve the desired change in fuel mixture. In most cases this will be a mass air flow (MAF) or manifold absolute pressure (MAP) sensor. In some cases, some other sensor such as the throttle position sensor (TPS) may be used. As load on the engine increases, the signal from the primary load sensor increases.
It is possible to tune the engine by altering the load signal in a precise way for all the different possibilities of load and RPM. Figure 2 shows a theoretical fuel map for an engine. The axes for the map table are load and RPM. The map contains numbers that represent the on-time in milliseconds. These numbers are not actual numbers that would be used to run an engine. They are calculated based on the total amount of time for one cam revolution.
These numbers are based on the time for a complete engine cycle at different RPMs. The actual pulse-width will be less than these numbers. Actual injector duty cycle rarely exceeds 80%.
In figure 3, a load trace is shown in red diagonally across the table. This trace roughly describes the path that would be followed if you were to gradually squeeze on the throttle and reached wide open throttle (WOT) at 8,000 RPM. As you travel along the diagonal trace, the pulse width increases from zero to 15.0 ms. For comparison, the blue trace shows the path you would trace by applying WOT from a low RPM. The green trace shows the path if you lift the throttle abruptly from 8,000 RPM.
Piggyback calibration can be achieved by varying the load reading to the ECU. Figure 4 shows an example range of adjustment. At any given RPM the fuel can be varied by changing the load reading to the ECU. The horizontal blue arrow shows the range of pulse width that can be achieved.
In this example the pulse-width is 12 ms at 5,000 RPM and can be adjusted from roughly 7.2 ms to 16.8 ms by varying the load signal by ±20%. While this example is based on theoretical numbers, it illustrates how varying a load signal can be used to change the amount of fuel delivered to the engine and the resulting AFR. When piggyback tuning by varying a load signal, what you are really doing is moving around on the stock map table. When doing this, you are fundamentally limited by the range of injector pulse width that is programmed into the stock ECU. For example, if the programmed injector pulse-width at a given RPM is only capable of reaching a 65% duty cycle, that is the maximum duty cycle you can get. This means you have to work within the range that the stock ECU gives you.
Load sensor adjustment is frequently used to compensate for larger injectors. At light load when the new injectors deliver too much fuel per stock programming, the load signal can be shifted to read a lower load which results in a shorter injector pulse-width.
There can be unintended consequences when doing piggyback tuning. The most important area of concern is ignition timing. In the process of adjusting the fuel mixture it is possible to change the load signal in a way that advances timing. In the extreme case, this can lead to engine damage. Figure 4 shows a theoretical timing map. Consider the same variation in load that was used in Figure 3 to adjust AFR and you see a substantial variance in ignition timing from roughly 25 to 35 degrees of advance. This is why calibrators for use in forced induction applications with larger injectors have the ability to retard timing as well as adjust fuel.
A typical example would be a naturally aspirated engine that has been converted to forced induction with either a turbocharger or supercharger. In order to fuel the motor in boost, it is fitted with larger injectors. The big injectors do a fine job of fueling the engine at the top end, but result in a mixture that is too rich in the light load region. To compensate for the large injectors, the load reading is modified according to an overlay map in the piggyback calibrator. Cell values are chosen in the overlay map that subtract a precise amount from the load signal. As a result the ECU provides less fuel to the engine by shortening the injector pulse width.
Closed Loop vs. Open Loop Operation
:
All engines with an O2 sensor are able to operate in closed loop mode. In this mode the ECU fine-tunes the fuel mixture as you drive. The actual fuel mixture is determined by one or more O2 sensors. These sensors may be narrowband, wideband or a combination of both. The narrowband O2 sensor is highly accurate at 14.7:1 which is known as the stoichiometric air fuel ratio (AFR). This AFR is targeted for the best compromise between fuel economy, performance and emissions. Stoichiometric AFR is essential to the proper operation of catalytic converters.
In closed loop mode, the ECU uses the readings from the O2 sensors to adjust the injector pulse- width to maintain stoichiometric AFR. This AFR is targeted during idle, cruise and moderate acceleration. The base fuel or nominal injector pulse-width is set according to air flow, RPM and environmental factors. The base fuel is modified according to O2 sensor feedback through a process called adaptation. Adaptation occurs both in real time and based on history. Historical adaptation data is stored in volatile memory that can be cleared by disconnecting the battery on the vehicle for 10 minutes.
A large part of the tuning process involves achieving stoichiometric operation over the light-load range. This is the range where we spend most of the time during daily driving. Tuning this region is essential to achieving good drivability. Tuning in the light-load region involves adjusting fuel for minimum adaptation as viewed on an OBDII scan tool.
ECUs that use narrowband O2 sensors need to be able to switch off the closed loop process to achieve enrichment. When the closed loop mode is switched off, the engine is operating in open loop. In open loop, the ECU no longer uses the O2 sensor to fine-tune the fuel mixture. Under high load conditions, the engine computer targets a richer mixture than 14.7:1 to safely support the combustion process. An AFR of 12.5:1 is typical for high load conditions.
Wideband O2 sensors produce precise readings over a wide range of AFR. ECUs that use wideband sensors are able to stay in closed loop over most of the load range of the engine. Rather than going open loop, the wideband based ECU can get enrichment by targeting a rich fuel mixture and trimming precisely to that mixture.
The OBDII Scan Tool:
One of the benefits of the universal OBDII standard is the availability of low cost diagnostic scan tools that will work on virtually all vehicles built after 1996. These tools are widely available from auto parts stores for $150 or less. Before you purchase one of these tools, make sure that it displays parametric data and is compatible with your vehicle. A scan tool is an indispensable tuning aid. Figure 1 shows the Autoxray EZ-SCAN 400 diagnostic scan tool which sells for around $350. It can read and clear diagnostic trouble codes, display real-time parametric data and can be updated as needed via the internet to assure compatibility with new vehicles.
Armed with a scan tool that can read engine data, you can tune the entire closed-loop region of operation. The process of tuning in the closed-loop region is one of minimizing adaptation. Adaptation is expressed as short term (ST) and long term (LT) fuel trim. ST fuel trim is an indication of the immediate compensation required to maintain the target AFR. LT trim is based on the history of adaptation acquired over up to 100 miles of driving. To determine the net trim add the two numbers together. Net trim can be used as a guide to adjust the fuel calibration in a piggyback engine management system.
The net trim is an indication of how much the ECU has to change the fuel to reach the target AFR. On a stock vehicle the net trim is normally in the +/- 5% range. If the net trim is a large positive number, it means that the ECU has to add a lot of fuel to reach its target. Large positive trims above 20% or so will result in a fault and diagnostic trouble code (DTC) for system too lean. A piggyback fuel calibrator can be used to add enough fuel in the region of interest to bring the net trim close to zero. Proper adjustment for minimum net trim throughout the closed loop region will give you optimum smoothness and drivability.
The Wideband Lambda Meter:
The single most important tuning tool is the wideband lambda meter. Particularly when mounted in a bung located in the pre-cat location, the wideband lambda meter will provide a highly accurate measurement of air fuel ratio. If is it not possible to locate the sensor in the pre-cat location, you can use a tailpipe clamp. The tailpipe method will usually match the pre-cat location reading within a variance of 0.3 AFR.
Lambda meters are available as handheld instruments or gauges that can be installed in the instrument panel. The Innovate Motorsports DB series gauges shown in figure 2 are available with either blue or red color displays.
A lambda meter may display either in the units of lambda or AFR. As such the meter may be referred to as a lambda meter or a wideband air/fuel ratio meter. The stoichiometric air/fuel ratio of 14.7:1 for gasoline is also known as a lambda of 1. Lambda is defined as L=AFR/14.7. Many meters are programmable so they can display with the units of either AFR or lambda. Table 1 shows some typical AFR values and the equivalent lambda values.
Throughout the closed-loop region of operation the AFR should be 14.7:1. As an engine is tuned in the closed-loop region there is usually no change in the AFR reading. This because the ECU adapts to changes to the base fuel and trims the fuel to its target AFR of 14.7:1 as needed. This is why the OBDII scan tool is used to tune the closed-loop region. The AFR meter is used to tune the open-loop region of operation. This normally occurs at high loads where the ECU is programmed to go into enrichment. A common target for enrichment at high load is 12.5:1 AFR.
The Tuning Process:
With the use of an OBDII scan tool and a wideband AFR meter, it is easier than ever to street- tune an engine for proper operation. Even if you have a dyno at your disposal, we recommend that you do a certain amount of street tuning. This is especially important to achieve good drivability under real-world conditions.
There is a logical progression to the tuning process. Generally you want to start with the light load region and work your way up to higher loads and RPMs. If you are working with a highly modified engine, you will first have to get the engine to start. You can then work on a good tune for the idle region. With a good idle tune you can get the engine to free-rev and crisply respond to throttle inputs.
Once the idle and free-rev regions are set, you can work on tuning the light load region by driving the car at a constant speed around 30 mph. Very little throttle input is required to sustain a constant 30 mph. Adjust the fuel mixture for minimum net fuel trim in the active region of the map table. The street-tuning process is vastly simplified by using two people. That way one person can watch the road, drive the car and hold the engine at various load points. The other person can concentrate on the scan tool, AFR gauge and tuning software. Use data logging that you can analyze later if you are tuning by yourself.
After the light-load region is set you can work your way up to higher loads. This is done by holding slightly higher and higher throttle positions. For each of these higher loads, adjust the fuel for minimum net fuel trim. Complete tuning the entire closed-loop region according to fuel trim. A well tuned closed-loop region will form a solid foundation for tuning the high-load region where the ECU goes into enrichment.
You can tell when the ECU goes into open loop by monitoring the fuel status parameter on the scan tool. Once the ECU goes into open loop, you can tune the fuel according to the AFR meter. Naturally aspirated engines are usually tuned for approximately 12.5:1 AFR at high load. Forced induction engines are usually tuned for a value between 11.0:1 and 12.0:1 depending on whether the engine is intercooled, has methanol injection and other factors.
Classic Pitfalls with Piggyback Tuning:
There are all sorts of ways to get into trouble when doing piggyback tuning. Some of the more common issues are described below.
- The engine runs but is hard to start: Piggyback calibrators must be connected to a reliable source of power during cranking. Many circuits are turned off by the unloader relay during cranking in order to provide maximum power to the starter motor. If you use one of those circuits to power the calibrator, the engine can be impossible to start. It is best to power the calibrator from the same switched ignition circuit that powers the ECU.
- The tune is unstable and changes when the headlights or accessories are turned on: Piggyback calibrators work by modifying signals. In the process of doing that, signals are measured, modified according to a mathematical operation and regenerated. The measurement and regeneration are done with respect to the ground wire. It is best to connect the ground wire to the sensor ground coming from the ECU. If you use chassis ground, your signal readings can easily be corrupted.
- The engine stumbles after it warms up: It is mandatory that you locate piggyback electronics in a location away from heat. The components are usually rated for the industrial temperature range which goes to 185 degrees F. It is not hard to reach that temperature in an engine compartment. It is best to locate piggyback electronics under the dash or elsewhere in the passenger compartment.
- The tach reading is jumpy: Tach inputs are frequently designed to work with square wave signals. These inputs can produce erratic readings when connected to an ignition coil. Due to the inductance of the ignition coil, the signal on the primary winding has a lot of ringing that can cause false triggering. In most cases the trigger pulse used in a coil-on-plug application can be used. Fuel injector signals can also be used to pick up a tach reading at the one-cylinder rate.
- Throttle response is sluggish: If your piggyback calibrator has a vacuum line, it is imperative that you provide a solid connection to manifold vacuum. Lines can be pinched or cracked especially going through the firewall. Use semi-rigid nylon line where possible and make vacuum lines as short as possible.
- The engine cuts out in boost: Many stock ECUs will go into fuel cut if either the MAF or MAP sensor reading exceed a maximum value. This results in an abrupt drop in power when you transition into boost. By carefully selecting the cell values in a programmable calibrator this problem can be avoided. The Split Second VC2 and VC2-5 voltage clamps are popular for limiting signals to within their normal operating range.
- The tune changes over the first few minutes of operation: This is a classic sign of an incorrect barometric pressure reading. Speed density ECUs that use a MAP sensor as the primary load sensor rely on the barometric pressure reading with key-on, engine-off to account for elevation change. If the calibration of the MAP sensor is not correct during the barometric pressure reading, the ECU will have to do a lot of fuel trimming when it goes into closed loop.
- The tune changes over the first hundred miles of operation: This is an indication that the ECU is adapting to your fuel curve. Even on a completely stock engine, the tune will change over the first one hundred miles of driving after the battery is disconnected. This adaptation is part of the self-tuning process that modern ECUs go through. The key when tuning is to look at the net trim which is the sum of the ST and LT fuel trim numbers. If you have a ST of -20% and an LT of +20%, you have a net trim of zero which is what you want. If you check the fuel trim at that load point after 100 miles of driving, both trim numbers should be close to zero.
- The real-time data does not match the map table: This can happen when the current file in your calibration software does not match the file in the calibrator. To synchronize the files you have to either read the file from the calibrator or write the file form the calibration software.
- The car dies when it comes back to idle: This can usually be fixed by adding fuel in the light load region at RPMs above idle and loads below idle.
Conclusion:
By now it should be clear that there are a lot of issues to consider when doing piggyback tuning. The reality is that there is even more to worry about. Not all piggyback systems are plug-and- play. Some require finding and splicing wires on the vehicle. This opens up the possibility of poor electrical connections that cause problems down the road.
A host of issues are caused by how you get power and ground. Some ECUs stay active for as long as a half hour after the ignition is turned off. During this time, sensor readings are checked. If the piggyback circuit does not have power, the ECU will set a fault for a bad sensor reading. Sensor ground is generally used when modifying sensor readings, while power ground is used when directly controlling injectors and high current loads. The use of the incorrect ground can easily cause faults or can even make the engine shut down abruptly.
Even with all the issues involved in piggyback tuning there is still a place for it in the realm of aftermarket engine tuning. Successful use of piggyback tuning can frequently offer the least expensive, or the only solution. Piggyback modules are often included as part of an aftermarket kit. Make sure you have installation instructions for your specific vehicle and follow them exactly. If you are doing your own thing, make sure you have the ECU wiring diagram for your vehicle so you can find the correct places for your connections.
Start your tuning project by determining your fuel strategy and selecting the components you want to use. Study the proper documentation for your vehicle and piggyback components.
Make sure that you have tuning tools that work with your vehicle and learn how to use them. Install your hardware carefully with high quality connections and double check everything. Take your time tuning starting with the light load region. Gradually work up to higher loads and RPMs. Watch out for detonation and avoid running lean. With a basic understanding of how an ECU works and what piggyback calibrators do, you can tune your engine for peak performance.
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