4"

 

The bigger the exhaust diameter the deeper tone the engine will have.

I got the corksport catback, I'd keep everything else stock size (2.5"?) till the catback, has a nice deep sound.

I got a N/A, on your turboII go with a 3" for sure, if you can go with 3" then try to get a 4" catback, or make your own and have the mid pipe flange? 3" -> 4"

I think that'd provide a deep sounding nice exhaust. I may be wrong though all I know is a turbo is less loud than a n/a so if you went with the corksport it wouldn't be that loud, I drove it for a few months w/out the silencer and never got one ticket.

 

well i see you live in cali... i live in michigan. we dont have the emission laws you have there first of all.. so i dont technically need a cat at all. the only thing we have here is if the car is really really loud and the cop feels like being a ***** he can give you a fix-it ticket.

i wanted to build the exhaust out of 3" pipe but now i dont know what to do for an exhaust or what to do about the wastegate.

 

a 4" setup will defintely have a nice deep sound. i run a 4" setup on my half bridge, its pretty loud at idle and when the car is under load, pretty nice at cruise. I do like the sound it is nice and deep.

 

and your turbo will spool faster

 

Depends on set-up... Only if you are moving enough gasses through the exhaust. In general a bigger diameter pipe will decrease backpressure, but going to big will decrease exhaust velocity, therefor increasing backpressure again.

You should calculate the ideal exhaust diameter for a certain RPM range, and then built one as straigh as possible with mandrel bends. At least that's what I would do if I weere to design a custom exhaust. **** how it sounds BTW... Guys are talking about Honda-sound and ricey-sound, discussing these topics IS rice! Performance is what should count, if you don't wanna be rice.

I would doubt a 4" exhaust on a stock TII would be bennificial (sp?). But if you think it sounds nice, and that's important to you, please go ahead. It will fulfill your needs.

Riz.

 

you really don't need a resonator with a 3" turbo RB catback. It's pretty damn quiet.

 

im not doing 4''... 3" will be fine. first thing i have to do is port the wastegate now that i know how to do that and why i need to.