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XIRMOVE
11-27-2007, 11:42 AM
Noob question, am I losing low end torque by switching to an aftermarket exhaust system (Greddy Titanium, Amuse, HKS Spec R, etc)? If yes, how much/noticeable?

mitdrx7
11-27-2007, 12:06 PM
Not at all. The best exhaust is no exhaust. The scavenging affect doesnt work the same way on turbo charged vehicles. You will take away some of the power robbing backpressure off the turbo.

SoCalRedLine
11-27-2007, 12:13 PM
exhaust gas velocity still applies eventhough you are trying to eliminate 'backpressure'

99.99% of all evo owners go with a 76mm (3") exhaust.

you will flow more overall exhaust CFM, but the velocity of the exhaust gas will be slower at low rpm (2.5-3K) than it would have been at with the stock diameter exhaust. So you will lose a bit of midrange, and gain a bunch of top end with the 76mm exh.

gas velocity properties FTW!

XIRMOVE
11-27-2007, 01:08 PM
exhaust gas velocity still applies eventhough you are trying to eliminate 'backpressure'

99.99% of all evo owners go with a 76mm (3") exhaust.

you will flow more overall exhaust CFM, but the velocity of the exhaust gas will be slower at low rpm (2.5-3K) than it would have been at with the stock diameter exhaust. So you will lose a bit of midrange, and gain a bunch of top end with the 76mm exh.

gas velocity properties FTW!


I'm planning to leave my Evo pretty much stock just improving areas which are lacking. I dunno if the stock exhaust system adequate?

SoCalRedLine
11-27-2007, 01:16 PM
in terms of ultimate high peak HP. No exhaust is best, like mit said. but anything from a 2.5" to a 3" will more than suffice as a good exhaust.

the main restrictions are the factory cat, a bit from the resonators, and the muffler.

ev0ninerr
11-27-2007, 02:35 PM
Just think more air=good. Yet, the parts restricting air flow are the exhaust, downpipe, IC piping, and use a drop-in filter(K&N or something just as good).

dabie
11-27-2007, 09:58 PM
you will feel a very noticeable increase in hp and torque with a full turboback..

JDMboi
11-29-2007, 06:56 PM
yes you will well worth it and nobody can leave a evo bone stock aint gonna happen thats what i said but i ate those words

ev0ninerr
11-30-2007, 01:18 AM
I'm still bone stock. lol.