Exhaust size

try to use jasma certified mufflers.. and a larger body housing of the muffler example s HKS super dragger II
 
for turbo,you should have 3 inches pipes from down pipe,highflow cat,midpipes to the muffler the inlet of your muff should be 3 inches too.. get a jasma certified muffler so you'll love the sound and not annoying noisy.. yet the performance is still there..the outlet of the muffler should be around 5-6 inches. 3 inches is the best size for turbo protege.. for NA is 23/8inches.
 
if you put p5 exhaust on a sedan, it will be few inches(~5.5inch.) shorter in the axle back piece
 
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