The most limiting part was apparently fuel pressure and the (size of the) injection valves. 

The engine in the GT2 RS was "capable" of way over 620 hp...just saying. Smiley

This doesn't say anything about the quality of the engines though. The modern Porsche engines are quite reliable and capable, if used within the factory (development) specs.


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RC (Germany) - Rennteam Editor Porsche 991 Carrera 4 GTS Cabriolet, Porsche Macan Turbo, Ford Mustang GT500 Shelby SVT (2014), Mini JCW (2015), Jeep Grand Cherokee SRT (2014)