Ignitions and Electrical› Wiring Harnesses

Psi

Vortec Engine Wiring Harness for Manual Transmissions

$579.99

SKU: HAR-G3WM

In Stock
In Stock
Ships by Jul 29
Free Shipping
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Advanced — 4+ hours

Description

The Psi HAR-G3WM is a standalone wiring harness designed for retrofitting 2003-2007 Vortec engines (4.8, 5.3, 5.7, 6.0-Liter) and T56/TR6060 manual or non-electronic transmissions into older vehicles. This harness supports the factory Vortec intake manifold and various injector types, offering a plug-and-play solution with a four-wire hookup.

Constructed with brand-new GM Delphi connectors and TXL high-temperature wire to GM specifications, the harness is professionally made and 100% quality inspected. It features a sliding grommet seal for a leak-proof installation and provides 4-5 feet of length from the cylinder head to the PCM mounting location. Transmission compatibility is flexible, as the computer and harness do not require transmission input for operation.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandPsi
Part NumberHAR-G3WM
CategoryIgnitions and Electrical

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

View Full Return Policy