Harness Conversion Services

OEM Reliability for Your Engine Swap

SVK Works • Stock ECU Solutions • Custom Wiring • All Chassis

The Ideal Solution for Stock ECU Builds

If you have purchased a JDM or donor engine that came with its stock engine harness and ECU, you don't need to go standalone to get your car running. Many enthusiasts prefer the drivability and reliability of the factory Toyota or Nissan ECU. Our services are designed specifically for people who want to implement that stock hardware into a new chassis while keeping every gauge and switch functional.

Wiring Logic

THE CONVERSION
Your Original
Chassis Plugs (Used from old harness)
+
Donor Engine
Stock Harness
=
Plug & Play
Swap
THE GEOMETRY CHECK
JDM Engine (RHD)
+
USDM Chassis (LHD)
=
Extension
Required

Service Options

Harness Conversion

Common for: MK3 Supra, S13/S14, E30, etc.

This service is for those using the stock ECU that came with their engine. We take the body-side connectors from your original car and professionally pin them into the donor engine harness.

  • Retains factory speedometer and tachometer signals.
  • Properly routes check engine light and diagnostic pins.
  • Ensures your stock ignition key triggers the starter and EFI relays.

Harness Extension

Essential for JDM-to-USDM Swaps

Stock JDM harnesses are designed for Right-Hand Drive cars, where the ECU sits on the opposite side. When putting these into a Left-Hand Drive chassis, the harness is physically too short to reach the passenger kick panel.

  • Avoids "stretching" the harness across the engine bay.
  • Each wire is extended using automotive-grade TXL wire.
  • Finished in high-temp loom to match the factory look.

Fixed Rate Pricing

While we work on various platforms, we maintain fixed pricing for most standard JZ and RB conversions.

Service Description Rate
Conversion Service Mating your stock engine harness to your chassis plugs $950
Extension Service Adding length for RHD-to-LHD configurations $450
Full Swap Package The complete solution (Conversion + Extension) $950 to $1,400