GM TBI CONVERSION KIT FOR 1987-1995 5.7L TRUCKS
***PLEASE NOTE THAT THIS KIT IS FOR OFF-ROAD USE, AND AS SUCH SOME EMISSION CONTROLS ARE
NOT APPLICABLE.***
NOTE: IT IS CRUCIAL THAT ALL INSTRUCTIONS BE UNDERSTOOD AND FOLLOWED TO ENSURE THAT
THE SYSTEM FUNCTIONS PROPERLY. FAILURE TO DO SO COULD RESULT IN SYSTEM FAILURE, AND OR
PERSONAL INJURY.
TABLE OF CONTENTS:
1 Introduction
2 Parts list
3 Step by step instructions
1.
INTRODUCTION
MOTORVATION has prepared this set of installation instructions for the installation of the GM TBI
CONVERSION KIT FOR 1987-1995 SMALL BLOCK TRUCKS. The purpose of these instructions is to provide
you with information that will allow you to make the conversion as safely and timely as possible. Please
take the time to carefully read the entire instructions, giving special attention to the areas marked
WARNING or DANGER as they contain information that, if not heeded, could result in the voiding of your
warranty, and or personal injury or death. Should you at any time need additional information or
assistance please call 1-901-275-2500 and ask for technical assistance. Our hours of service are:
Mon.-Thurs. 8:30am to 5:00pm, and Fri. 8:30am to 12:00pm (all times listed are CST)
***Please have the part number of this product available when making this call in order to expedite this
process.***
WARNING! THIS KIT CONSISTS OF MANY DIFFERENT PARTS. FAILURE OF ANY SPECIFIC PART DOES NOT
RESULT IN THE WARRANTY OF THE COMPLETE SYSTEM. INDIVIDUAL PARTS ARE AVAILABLE FOR
REPLACEMENT.
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WARNING! ALL WORK SHOULD BE PERFORMED IN A WELL-VENTILATED AREA. EXTREME CAUTION
SHOULD BE TAKEN TO ENSURE THAT NO FLAMMABLE, OR POTENTIALLY FLAMMABLE SOURCES ARE
PRESENT OR INTRODUCED DURING THE UNDERTAKING OF THIS INSTALLATION. FAILURE TOM DO SO
COULD LEAD TO AN EXPLOSION OR FIRE, RESULTING IN DAMAGE TO PROPERTY, PERSONAL INJURY,
AND OR DEATH.
2.
PARTS LIST
Please check carefully to ensure that you have received all of the necessary parts needed for completion
of this installation.
Itemized Parts Description
Part
Description Quantity
1.
TBI Assembly 750cfm w/ fuel rails, injectors, regulator,TPS, and IAC
2.
Intake Manifold
1
1
3.
TBI Flange Gasket
2
4.
Intake Manifold Gasket
1
5.
Throttle and Cruise Control Bracket
6.
Throttle/Cruise Control lever Stud (installed on throttle lever)
7.
1
Transmission Kick-down Stud
8.
10’- #6 Fuel Hose
9.
#6- Straight Hose End
10.
#6 - 90 deg. Hose End
11.
#6 to 14mm-1.5 male O-ring Fitting
12.
1
1
1
2
2
1
#6 to 16mm- 1.5 male O-ring Fitting
1
13.
#6 to 16mm -1.5 female O-ring Fitting
14.
1 Foot of ½” Vacuum Hose (brake booster)
15.
Hardware
16.
Certificate for Computer Chip for Application
1
17.
Motorvator Spacer Plate
1
2
18.
Sensor Adapters (TPS, and IAC)
19.
Injector Connector
ea.
1
1
NOTE: Many items listed above have been pre-assembled for your convenience.
ADDITIONAL ITEMS REQUIRED FOR INSTALLATION

0-60 psi or higher fuel guage

Tee fitting for fuel guage
3.
STEP BY STEP INSTRUCTIONS
1. Disconnect the battery.
2. Replace Fuel Pump located in the fuel tank. NOTE: It is recommended that
Chilton’s manual or have this work performed by a certified mechanic.
you use a
3. Make a diagram of the vacuum hose routing prior to disconnecting any vacuum hoses.
It is highly recommended that you label all hoses, vacuum sources, and usable ports before
attempting to remove any of the existing fuel system.
4. Remove the fuel line connecting the original throttle body to the fuel filter, and the union for the
return line that runs along the frame. Dispose of this line properly as it will not be needed in the
installation of your new system.
5. Disconnect electrical connectors at the sensors, distributor, and coil. Then, remove the distributor
and coil from the engine.
6. Remove the existing intake manifold, along with the throttle body. It is recommended that you place
a clean rag or clean shop towels in the intake ports of the cylinder heads, as well as the lifter valley,
to keep any debris out of the engine. Be careful to keep the ends of the vacuum and fuel lines from
coming into contact with dirt or debris.
7. Carefully remove all of the old gasket material from the cylinder heads, taking special care not to
scar the flange of the head where the new gasket will be positioned. If any material is not removed,
or if the surface is damaged during cleaning, the gasket will not seal properly.
Make sure that the surface is clean and dry before installing the new gasket.
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8. Discard the rags or cleaning towels that were used to protect the intake ports and lifter valley.
Inspect the area and all openings to make sure that no dirt or debris remains.
9. Install the new MOTORVATION 4BBL intake, spacer, and throttle body using the provided gaskets
and the original intake bolts. Make sure they are used in the same location, for proper bracket
mounting.
NOTE: IT IS OK TO USE GASKET SEALENT TO PREVENT ANY
POSSIBLE LEAKS.
NOTE: THERE IS NO PROVISION FOR THE EGR VALVE IN THIS
INSTALLATION
(THIS IS FOR OFF-ROAD USE ONLY).
10. Remove the ignition coil from its original bracket. It may be riveted and may need to be drilled to
remove. Mount the coil on the MOTORVATION throttle bracket using the supplied screws and nuts.
11. Attach the throttle and cruise control cables to the throttle body. If the truck is equipped with a
700R4 transmission, the throttle valve cable must be connected to the lower arm on the throttle
linkage. It may be necessary to make adjustments to the throttle valve cable for correct transmission
functions. Use the provided return spring, attaching it between the throttle bracket and the throttle
linkage.
CAUTION: FAILURE TO PROPERLY ATTACH THE THROTTLE RETURN SPRING COULD LEAD
TO THE THROTTLE STICKING OPEN. IMPROPERLY INSTALLED THROTTLE CABLES,
LACK OF PROPER CLEARANCE FOR ANY PART OF THE THROTTLE LINKAGE, OR A BINDING
THROTTLE LINKAGE COULD RESULT IN PROPERTY DAMAGE, INJURY OR DEATH . ALWAYS
CHECK THE OPERATION OF THE THROTTLE, WITH THE ENGINE OFF, TO MAKE SURE IT IS
FUNCTIONING SMOOTHLY, AND FREE OF RESTRICTION.
12. Refer to the diagrams that you made, as instructed in step 3 of the instructions, before removing the
vacuum hoses. Install the vacuum hoses to the correct port on the throttle body.
NOTE: Since the EGR valve has been deleted, the EGR vacuum sources can be deleted.
13. Put the supplied 16mm-1.5 male fitting into the fuel filter .
NOTE: It is recommended that a new fuel filter be used.
14. Put the supplied 16mm-1.5 female fitting on the return line.
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15. Install the 90 deg. hose end on one end of the supplied hose. Temporarily screw the hose onto the
throttle body at the fuel rail. Route the hose toward the firewall. Proceed down the driver’s side
frame, routing the hose in the same location that the original fuel lines were located. Measure the
line at the fuel filter and mark it. Cut to length and install the straight hose end. You have now
completed the new feed line, or fuel pressure line that connects to the throttle body.
16. On the remaining fuel hose, install the 90 deg. hose end and temporarily screw to the fuel pressure
regulator. Then, route along the pressure hose to the union and measure to cut. Put on the straight
hose end. This will complete the return fuel line.
17. Check and recheck all connections on the fuel lines for tightness.
WARNING: ALL FUEL LINES MUST BE ROUTED AS FAR AS POSSIBLE FROM DIRECT HEAT
SOURCES TO PREVENT POSSIBLE EXPLOSION OR FIRE.
18. Install distributor and plug wires. Make sure the engine is set at 0 deg. Top Dead Center on
cylinder #1 for proper timing.
19. Connect the TPS and IAC connectors. Some models may require the use of the supplied
adapters. If the TPS adapter is needed, splice the wire as shown in the following diagram labeled
19a.
20. Connect the injector harness to the injectors. It is necessary to splice the 4 original injector wires as
shown in the following diagram labeled 20a.
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21. Reconnect all cooling hoses and install the alternator brackets and wires.
22. Reconnect battery connections.
23. Cycle the ignition switch to prime the fuel system, and verify that there are no leaks.
Using a fuel pressure gauge, set the fuel pressure to 50psi by adjusting the regulator as necessary.
24. Using either a voltmeter or a scanner, set the TPS sensor voltage to .5-.9 volts.
25. Install the MOTORVATION computer chip using instructions supplied with the chip.
26. Crank the engine. Set the timing by disconnecting the timing bypass wire to original
0 degrees BTDC. Turn off the engine.
27. Restart the engine and allow it to reach operating temperature. Using a scanner, watch the IAC
counts. Set the idle adjustment screw on the throttle body so that with no load on the engine, the
count is between 10 and 20. This will allow the IAC to have full range to open when a load is applied
to the engine. It is necessary for the IAC to open to allow air into the engine in order for the engine
to maintain idle speed.
28. ENJOY YOUR NEW 4BBL POWER !!!
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