Precision Wiring.
Built for Performance.
Standalone wiring harnesses engineered from scratch for your build. Clean, reliable, and race-proven — from street to track.
Find Your Harness
Browse standalone wiring harnesses by vehicle platform or engine type.
Popular Harnesses
Our most requested standalone wiring harnesses, built to order.
PopularMK4 Supra 2JZ-GTE Standalone Harness
Complete standalone engine harness for the 2JZ-GTE in the MK4 Supra chassis. Plug and play with OEM connectors.
PopularMK3 Supra 2JZ-GTE Swap Harness
2JZ-GTE swap harness designed for the MK3 Supra chassis. Full standalone with all chassis integration.
Custom OrderK20/K24 Universal Swap Harness
Custom standalone harness for Honda K20/K24 engine swaps. Built to your specs — contact us for a quote.
Custom Order1UZ-FE Universal Swap Harness
Universal standalone harness for 1UZ-FE V8 swap into any chassis. Built to your specs — contact us for a quote.
PremiumMil-Spec Autosport Firewall Connector
Motorsport-grade Autosport quick-disconnect firewall connector with CNC metal mounting plate.
NewMK4 Supra 3D Printed Cupholder
Custom 3D printed cupholder designed to fit the MK4 Supra (JZA80) interior. Drop-in fitment with no modification required.
Built Different
Every harness is designed, built, and tested by hand in-house.
Mil-Spec Wiring
TXL cross-linked polyethylene wire rated for automotive temperatures and vibration. Raychem Spec 44 available for race builds.
OEM Connectors
Genuine OEM-quality Toyota, Sumitomo, and Deutsch connectors. No cheap knockoffs — every pin fits like factory.
Plug & Play
Designed for your specific chassis and ECU combo. No guesswork — plug it in and start tuning.
Custom Built
Every harness is built to your exact specifications. Custom lengths, custom ECU pinouts, and tailored chassis integration.
What Builders Say
"Best harness I've ever installed. Plugged right in, fired up first try. The quality of the wiring and connectors is unmatched."
"The MK3 2JZ swap harness saved me weeks of wiring. Everything integrated perfectly with the gauge cluster and AC."
"Race-grade quality at a fair price. The K24 harness weighs nothing and the autosport connectors are legit. Competition ready."
"The SC400 harness made the CD009 swap so much cleaner. No weird workarounds — everything from the speedo to the reverse lights worked first try."
"Ordered the 7M harness for my MA70 build. Super clean, all labeled, and the build quality is miles above anything I've used before. Highly recommend."
Tech Articles & Guides
Build knowledge from the SVK workshop — wiring tips, swap guides, and tech deep-dives.
Why Your Build Needs a Standalone Harness
Still running a modified OEM harness? Here's why going standalone is the best investment for your build.
MK3 Supra 2JZ Swap: Wiring Considerations
The 2JZ swap into the MK3 Supra is legendary. Here's what you need to know about the wiring side.
Choosing the Right ECU for Your 2JZ Build
Haltech, Link, AEM, Motec — our breakdown of the most popular ECU choices for 2JZ builds.