Performance • Power • Drivability
Professional performance remapping, gearbox tuning and vehicle software solutions across Essex and surrounding areas.
Built for performance
SX Customs helps drivers unlock stronger power delivery, sharper throttle response and better everyday drivability through tailored ECU and gearbox tuning solutions.
Whether you want a smoother daily diesel, a sharper petrol turbo, improved gearbox behaviour or diagnostic support for vehicle software faults, we keep the process clear and professional.
Serving Essex, Chelmsford, Basildon, Brentwood, Southend, Thurrock, Colchester, Braintree, Romford and surrounding areas.
Our services
Power, torque and response improvements for standard vehicles.
Custom tuning for modified cars with supporting hardware.
Sharper gear changes and improved drivability.
Diagnostics and software solutions for permitted uses.

DPF diagnostics and specialist software support.
Reliability-focused EGR diagnostics and solutions.
Local coverage
These pages target the local searches your customers use, including mobile remapping, Stage 1 remaps and tuning services in towns across Essex.
Ready to tune your vehicle?
Message us with your registration, engine size, current modifications and what you want from the vehicle.