eddierotary

iTrader: (7)

hi

i have a question because i have a SP S4 turbo II engine with S5 stock/mod turbo that im planning to put on my GTU soon and i was looking for ways i can keep my stock exhaust ( stock cat back) i was thinking of juts putting my RB 2.5 inch down pipe and presilencer with stock muffler and my question is how much does it hurts HP and performance of the engine? like how much horsepower im losing compare to a 3 inch exhaust or a RB catback with the downpipe i have. because i wanna keep my stock muffler because they are quiet plus i dont wanna have problems with law (cops dont like loud cars around here) plus i heard of too many people complaning about boost creep with 3 inch exhaust and i think 2.5 will keep the boost down, well at lease i think. thanks

eddie

eddierotary

iTrader: (7)

i hope you guys can understand my question

Rancid7

obviously you'd make more power with a 3" turbo back , but with the 2.5" downpipe and the rest stock you should have solid boost control and should still make decent power . Your turbo also wont spool up as fast as it would with the 3" exhaust but you wanted quiet right ? i'd say try it out and see how you like it . If you feel that its too restrictive check out the racing beat pre-silencer and cat-back . its pricey but worth the money , it offers the best of both worlds : quite and performance .

bcty

totally if you can get the full RB system. Since your useing the stock turbo it will bolt right up. It sounds stock and preforms way better so its a no brainer, if you have the money that is..

FB II

exhaust severely effects turbo rotaries. if you keep stock everything minus downpipe you might as well not even use the downpipe.

eddierotary

iTrader: (7)

so with just the stock Y pipe and mufflers will retrice alot? not that i dont like noise because my old FB had the same setup but with a mindtrain exhaust and i loved it and it was wicked loud pass 5K RPM sometime louder that my 140 db sound sistem at half way and i think that was loud and now i have a 7 month old kid and i dont wanna ruin his ear drum right now. that why i wanna keep it quiet, but ill see how it works and thanks for your opinions