The Cup car, the GT3R and the RSR basically runs the same motor in the GT3RS.

In Cup car trim, the engine actually make less HP, rev limit is also lowered. ~485HP

In GT3R trim the motor makes the most power ~560HP

In RSR trim, the power goes back down to ~510HP. 

GT3R and RSR need to run restrictors so yeah, 600HP is possible.


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