PERRIN EVO X Turbo back build...
Jeff,
AMS didn't make any power (so they say) with the Down Pipe alone, they tried
2.5", 3", and 3.5" if I am not mistaken.
When they made the o2/downpipe combo though, they did make power, as the o2 pipe is very restrictive.
Buschur also notes that the biggest gain in the exhaust system, other then the catback, would be the o2 housing.
Please look into this, as I and a lot of others would be interested in purchasing .
Thanks,
Chris
AMS didn't make any power (so they say) with the Down Pipe alone, they tried
2.5", 3", and 3.5" if I am not mistaken.
When they made the o2/downpipe combo though, they did make power, as the o2 pipe is very restrictive.
Buschur also notes that the biggest gain in the exhaust system, other then the catback, would be the o2 housing.
Please look into this, as I and a lot of others would be interested in purchasing .
Thanks,
Chris
I think we didn't see as much gain as we were testing our parts with a tuned map to start with. So we were much closer to maxing out the airflow the turbo.

It is a very good representation of the sound!
Last edited by PERRIN_Jeff; Jun 26, 2008 at 10:33 AM.
How much power can the CBE support? With the 90degree bends and the center muffler I wouldn't think it's as free flowing as straight pipes....so can u supply and back pressure related info and what it can support?
funny!
Is there any way to extend the tips back further to hide where the smaller tubing meets the huge 4" tip. From an angle, it looks horrible, like some kid tacked on a huge rice can tip to a wimpy exhaust pipe!
Seriously we used this same basic muffler setup on another car making 450WHP and it made the same HP at the same boost level as a similar car with a straight through muffler. Even though the air makes a turn its all very open and free. This was on an STI with a GT3076R turbokit. I just comes down to how restrictive the internals are. And the muffler you see is like 2 straight through mufflers, but instead of connected with a y, its connected with a big chamber.
We can supply some back pressure numbers, not a problem, but not sure how this is going to help when no one else has these numbers to supply. Give us a little while and we can do that.
Final production pieces will have a different transition there and it will hide that slightly. Good suggestion!


