ECU & Power Restrictor Overview

With a greater emphasis of torque within Gran Turismo 7, torque should be a high priority when applying engine upgrades or restricting power. 

When reducing Fully Customisable ECU %, it equally reduces power and torque with no change to the the power and torque curve.

When reducing Power Restrictor %, it primarily reduces peak power. There is only a reduction in peak torque, if peak torque RPM is close to peak power RPM. This means torque at low RPM is not affected by the Power Restrictor %. The power and torque curve will become steeper in relation to the Power Restrictor % reduced. This may reduce top end performance and reduce top speed. This is because peak power RPM is also reduced.

To get optimal performance for Performance Points (PP) it is definitely worth experimenting with these % values. There are 2 specific instances where one option is more preferable over the other.

The following 2 instances are only most noticeable with under ~550bhp outputs.

• When the Fully Customisable ECU also increases maximum RPM, the top end performance when reducing the Power Restrictor % isn't as prominent, compared to when the ECU has no effect to maximum RPM.

• When the Fully Customisable ECU has no effect to maximum RPM, in most cases it is beneficial to reduce ECU % rather than reduce Power Restrictor %. This is because without the increased maximum RPM from an upgraded ECU, the power and torque curves will peak at lower RPM reducing high RPM performance.

• The lower the Power Restrictor % reduced, the bigger the increase in performance gained between ECU % and Power Restrictor when building to the same Performance Points (PP).

The following test will show that when building vehicles for specific power outputs, the use of Power Restrictor % is best so long as the limiting power output is high enough.

For this test, i used the Nissan R34 GT-R V.spec II Nur '02 with the following additional parts:

• Engine Swap

• Power Restrictor

• Fully Customisable: Racing Transmission

• Racing Soft Tyres

All of these parts were chosen to enhance the effect of an optimised flipped gearbox.

From there i reduced the performance of the vehicle down to ~660PP with only the use of the reduction of ECU% or Power Restrictor %.