Result as belowStock exhaust valve close 98 dBStock exhaust valve open 102 dBEvolution exhaust valve close 104 dBEvolution exhaust valve open 119 dBF1 exhaust valve close 106 dBF1 exhaust valve open 123 dB.
 
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GMG World Challenge Track Spec - 2011 GT3RS 3.8 to 4.0 engine build. This is GMG 4.0 liter stroker engine conversion available for all GT3 / RS - Turbo and GT2 , 996 and 997 base models.
 
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Four Porsche GT3 RS 4.0 at the track, These cars have the stock exhaust but are still very loud.
 
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Four Porsche GT3 RS 4.0 at the track, These cars have the stock exhaust Porsche Ring TAXI with different models of Porsche giving passengers a ride around the track.

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Porsche and other cars video collection