
Engine Compatibility:
This engine wire harness is designed for use with any Small-Block Chevy (SBC) engine with 1985-1992 Tuned Port Injection (TPI) intake manifold. Aftermarket multi-port injection intake manifolds may require the use of extension and adapter harnesses. Popular aftermarket multi-port intake manifolds include:
- Holley Stealth Ram
- TPIS Mini Ram
- Accel Super Ram
- FIRST TPI
- Edelbrock Pro-Flo XT
- GM Ram Jet 350 (consider using AWP-7001)
Ignition System Compatibility:
The ignition connection on this harness is a 10 cavity sub harness connection that mates to several different Holley ignition sub harnesses.
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GM Small Cap HEI Distributor |
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GM Large Cap HEI Distributor |
Wideband Oxygen Sensor (WBO2) Compatibility:
This harness includes an 8 cavity connection for the following WBO2 sensors compatible with the HP and Dominator ECUs.
- 554-100 NTK Wideband Oxygen Sensor
- 554-101 LSU4 Bosch Wideband Oxygen Sensor
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This harness also includes adapter harness AWP-6003 for the following WBO2 sensors compatible with the Terminator X and Terminator X Max ECUs.
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WBO2 sensors are sold separately.
30A Main Power Harness for Holley EFI ECUs Included:
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This harness also includes a Main Power Harness AWP-6004 that can be used with all Holley EFI ECUs. |
Compare to Holley 558-503 GM TPI/STEALTH RAM EFI HARNESS KIT:
- Holley retail price is greater than $713.00.
- 558-503 requires a separate EV1 fuel injector harness. Included, but not integrated.
- 558-503 requires a separate ignition system harness. Included, but not integrated.
- 558-503 requires a knock sensor harness not offered by Holley.
- 558-503 does not include a powered CAN bus connection.
- 558-503 does not include a firewall grommet.
- 558-503 requires the additional purchase of an oxygen sensor adapter harness when using Terminator X and Terminator X Max ECUs.
Emissions
The sale or use of this harness is only legal for vehicles purposed for off-road use. It is against the law to use this harness on a vehicle registered for street use.