turbo-back exhaust question

[zvilly]

Hi everyone,

 

So after reading CObb's article on turboback exhaust, they come to one of the conclusions: the further downstream you neck down the exhaust the better.

 

So, I am considering an exhaust design that consists of a catless up-pipe, catless downpipe, stock 3rd cat, stock piping after the 3rd cat and two magnaflow mufflers.

 

Is anyone running something to a similar setup above? Would I have problems with overboosting with a catless downpipe even though I have a stock 3rd cat (in the midpipe) ?

 

Reason I'm considering keeping the stock piping after the 3rd cat is strictly for cost reduction and that i want to get to Stage 2 pretty badly

 

Thanks!

 

-Villy

[NSFW]

That stock 3rd cat should be more than sufficient to mitigate overboost. I have a single high-flow cat and no overboost problems.

 

I suspect that you'd get more power with the stock mufflers and a single high-flow cat in the downpipe.

 

If you're OK with the environmental impact, consider skipping the magnaflows and just getting a 3" catless downpipe (delete all cats). You may be able to find a used catless DP for pretty cheap.

[zvilly]

I've though about going completely catless, but I'm worried about the smell more than anything. I don't want my clothes to stink after a drive to work

[05gtlimited300]

i ran a shorty, stock 3rd cat and xo2 catback w/o any issues. now i have the invidia catted DP no problems also

[goneskiian]

Many folks simply gut the first cat after the turbo to go stage 2. Oh yeah, a catless UP is also a good idea if you've got an '05. Although, NOWHERE in COBB's literature does it state that you must have a catless UP to go stage 2.

 

Cheers!