Main Harnesses

Main Harnesses

The main harness carries all sensor inputs to and control outputs from the Holley Engine Control Unit (ECU). It does not carry power and ground for the ECU (see ECU Power Harness). It is meant to carry the signals from the location of the ECU (commonly in the driver compartment) to the engine compartment. The Main Harness connectors inside the engine compartment do not typically connect directly to the components there, but connect to a sub-harness for that component. This allows a single Main Harness to be customized to work with a huge combination of different injectors, ignition components, and sensors. (See Injector Harnesses and Ignition Harnesses.) The Main Harnesses included in kits are customized for that kit, and can be purchased separately for replacement. The Dominator ECU does not include a Main Harness, so it must be purchased separately. All Main Harnesses will fit all Holley ECU's.

Choose From:

Show:
Sort By:

Main Harness, 99-04 Ford Godzilla 7.3L

EFI Main harness for the Ford Godzilla 7.3L Engines. Note that two different ignition connector styl..

$520.95 $462.95

Main Harness, 99-04 Ford Modular

Main harness for 99-04 2 & 4 Valve Ford Modular (4.6 & 5.4L) Engines. Note that two differen..

$844.95 $750.95

Main Harness, Gen III Hemi w/Early Crank/Cam Sensors

Check the alternate image above to see the difference between the early and late cam and crank senso..

$871.95 $774.95

Main Harness, Gen III Hemi w/Late Crank/Cam Sensors

Check the alternate image above to see the difference between the early and late cam and crank senso..

$826.95 $734.95

Main Harness, LS1 / LS6

This harness is designed for Chevy LS and late-model truck engines that have a 24-tooth crank sensor..

$653.95 $580.95

Main Harness, LS2 / LS3 / LS7

This harness is designed for Chevy LS and late-model truck engines that have a 58-tooth crank sensor..

$653.95 $580.95

Main Harness, Multi-point / Stealth Ram

If you need to replace one of the Holley Stealth Ram system harnesses, or if you are building a stea..

$653.95 $580.95

Main Harness, Terminator

Replacement main wiring harness for Terminator EFI kits 550-405 and 550-406...

$518.95 $460.95

Main Harness, Unterminated Universal

If you are looking at this harness then you are obviously forced down a difficult road! You may wan..

$546.95 $485.95

Loading...