The ST205 Celica GT-Four is a legitimate rally car, and it deserves engine management built to match that pedigree.
The 1999 Toyota Celica 3S-GTE ran a purpose-built AWD platform with the 3S-GTE in its most developed form, but factory ECU management still left power on the table. The Tuned By Shawn Boomslang PNP Wiring Harness for the Haltech Nexus connects directly to your factory harness without any permanent modifications, giving the Haltech Nexus full standalone engine control. No cutting, no splicing, fully reversible.
Advantages
- Boost curves tuned to your actual turbo, not Toyota's conservative stock map
- Throttle response that's immediate and consistent at all temperatures
- Power delivery that matches what the 3S-GTE is actually capable of with your setup
- Stable fueling under the high-load conditions this car was built for
- Confidence on track that your tune was built for your exact conditions
Features
- Plug-and-play fitment for 1999 Toyota Celica 3S-GTE, manual transmission
- Compatible with Haltech Nexus R3, R5, S2, and S3 ECUs
- No cutting or splicing of factory wiring
- OEM-quality connectors, USA-built by Boomslang Fabrication
- Fully reversible, factory harness preserved
- For competition and off-road use
The Details
Built specifically for this vehicle's connector layout with OEM-spec connectors and correct wire gauge throughout. Your factory harness stays completely untouched and the car can return to stock at any time. The Haltech Nexus takes full engine control once installed, giving your tuner a clean vehicle-specific foundation to build a proper map from.
Kit Includes
- 1x Boomslang PNP wiring harness for 1999 Toyota Celica 3S-GTE
- Haltech Nexus ECU sold separately
Fitment
1999 Toyota Celica 3S-GTE, Manual Transmission.