Comparison tests Audi S4 v Audi RS4. Does Supercharging Rule? - CHRIS HARRIS ON CARS

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Btw, cant wait for the R8 V10 Plus test, as Chris mentioned!

 

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One more thing to take into consideration is linearity. Suppose you have a turbocharged engine that has a 0.4bar of constant pressure with a 0.6bar of overboost between 3500 and 5500rpm. You can easily go to an ECU tuner and increase the boost pressure up to 1.2/1.4bar or even more. Sure, you get a very descent power increase, but your engine is nowhere as linear as it used to be.

True for turbocharged engines but the S4 is supercharged and most of the additional power ( for stage 1 remaps) is generated by keeping the waste gate closed to 7000 rpm instead of 5500rpm, so all it's really doing is increasing peak power at 7000rpm. Obviously, this puts additional strain on mechanical components and generates more heat, the gearbox and rear diff will break before the engine in most cases.