Derived from the XR3i, the RS Turbo adopts an intercooled Garrett Airesearch TO3 turbocharger providing a maximum boost pressure of 0.5 bars and is equipped with electronically controlled Bosch KE Jetronic fuel injection. Internal modifications to the 1.6 CVH engine include new pistons, strengthened and reprofiled to lower the compression ration from 9.5 to 8.3:1 high temperature sodium cooled Nimonic alloy exhaust valves and revised inlet and exhaust porting. The RS Turbo was fitted with an engine control system (ESC II), which features electronic management of both ignition and turbocharger boost pressure.By reference to a calibrated multi-point ‘map’, the pressure signal to the Turbocharger waste gate is modified by the microprocessor, tailoring boost to operating conditions and providing three important safety features: avoidance of engine knock (or detonation) by automatic boost reduction: fuel cut-off (at 6400 rpm) and ignition cut-off (at 6500 rpm).
Revised valve timing and engine development have provided an extremely flat and useable torque curve for a turbo engine. Boost pressure is detectable as low as 1000 rpm and at 2200 rpm torque is equivalent to the maximum developed by the XR3i (138 Nm). Peak torque for the turbo is 180 Nm, achieved at 3000rpm.
The up rated braking system and sports suspension with Girling gas shock absorbers all round was derived from the RS1600i. To reduce wheel spin and improve handling the RS Turbo also features a viscous coupled limited slip differential which used a silicon fluid in shear to control the torque distribution between the front wheels. The smooth build up of shear forces in the fluid locks the differential progressively as the wheel spins faster. This provides a much smoother differential lock than a conventional mechanical system, eliminating interior vehicle noise improving traction, handling and benefiting front tyre life.The Escort RS Turbo came in just one colour for the general public with the full colour coded body parts (bumpers, mirrors and rear wing etc.) There was two Escort RS Turbo’s specially produced. They were both painted black. One of the particular black Escort Turbo’s was presented to HRH, The Princess of Wales. This particular car still exists to this day.