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Discussion Starter · #1 ·
Hey guys and girls, Iv searched around a little and couldn't find what i was looking for so ya. Iv been debating whether to replace my stock cat back to finish off my exhaust. I already have a 42DD 3" catless downpipe, with a resonator delete. Would buying the rest of the 3" 42DD catback be any notice at all? In any aspect? Im guessing they would be minor gains if any. Id just like someone else input to help along my decision.
 

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Performance gains, probably not. It will sound a lot better though. I had the same setup you did (except I had the cat), got the 42DD cat-back and had no noticeable performance gains, but the sound is priceless.
 

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Discussion Starter · #3 ·
Yea I figured with the gains. Iv seen your video on youtube of your Drive by and inside. It does sound amazing. But im interested to see what it would sound like catless? Because i know that could make a big difference. any ideas?
 

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It really wont make a huge difference, maybe a little more throaty at high RPMs
 

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Discussion Starter · #5 ·
Alright, Thanks for the reply's
 

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Turbo-back and cat-back are 2 different things.

The main component that will gain you performance is the downpipe which is the first half of a turbo-back. The reason you get gains is because you replace a downpipe that has 2 heavy cats with a single high flow cat (or no cat at all). In addition, the first cat on a stock downpipe is about 6" from the turbo. This causes a bit of restriction for the turbo and does not allow it to spool up as quickly or as fast as it could without it there. In addition, replacing the downpipe portion allows you to get a tune beyond Stage 1.

The second half (cat-back) does not yield noticeable performance gains, its more for looks/sound. This is why we recommend just doing the downpipe first, get the tune you want and when funds allow you can pick up a cat-back.

Hope this helped.
 

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I have same set up except on mkiv.With windows up i can barley here it under noirmal driving but windows halfdown and full throttle sounds pretty angry..So its perfect, sure I wish it could be a lil louder, but i almost always am blasting music...and 3in all the way gonna be rea loud, i dont really want more attention.
 
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