I have a Good-Win Racing RoadsterSport II exhaust on my miata currently. Will I have to upgrade the exhaust when i start running boost? I am going with an EVO X 18G turbo setup, custom mani, etc... But I LOVE my RS2 exhaust. I dont want to part with it, but in the name of it not exploding due to the tremendous pressure of forced induction I will upgrade/change it out if necessary. What do you guys think? I cant seem to find anything about people running this exhaust with a turbo setup, actually it seems rare enough that I cant find much of anyone running it at all lol.

 

I mean it won't explode... but it will limit power and the turbo alone will modify the sound.

 

should be ok the worst that will happen is low hp and bad spool

 

The RS2 is a 2.25" setup, and it will sound exactly NOTHING like what it sounds now when you put the turbo on it, so forget about "loving" the sound. You can have a 3" stainless catback or cat-delete exhaust fab'd up at any respectable speed-shop for under $400... some guys are finding places that do exceptional work for around $300... shop around, ask your buds, drop names.

The difference betwee a 2.25 and 3" on an 18g will probably be about 500rpm of spool and 10-15whp at 10-12psi, with an equal loss in torque... just a guess.

 

Just going from a stock exhaust to a 2.5" crimp-bent small shop exhaust made a big, noticeable difference on my 2560 with only 8 psi. Earlier spool, more power. Now I have a 3".

 

Turbos change the sound of your exhaust. That's why it won't sound the same. The turbo could be thought of as a circular muffler with spinning blades inside instead of fibreglass etc..

 

torque(ft*lbf)*rpm(s^-1)/5252