libertyforall1776

iTrader: (2)

What replacement exhaust pipe size would you all recommend and why? Looks like some are 2.5" and some 3", etc. Any particular brand? '11 CTS-V, assume CAI, plan to replace entire exhaust, add headers and NoWeeds.net exhaust diverters.

Also looking for a recommendation on Header pipe sizes?

No it's not mine, but for a family member... TIA!

libertyforall1776

iTrader: (2)

69 views with not a single shred of inputs from anyone?

ColeGraham

iTrader: (8)

Most guys on this bored are V1 owners...if your family member not a check out www.ctsvowners.com ...there is a lot of good info on there for the 2009+ V. Or you can check it out for them...haha

That site is more geared to the 2009+ V crowd.

To answer your question, when I swap my exhaust going with long tunes, factory cat back, and cut outs.

For full exhaust, Sainless Works has long tubes with 2" primary's and a 3" cat back. Then you have kooks and American racing for long tubes for the 1 7/8". Cat backs I have seen are magnaflow, corsa, and Stainless works.

For what to run, it really doesn't make a difference, unless you plan on a bigger blower, high psi, and/or more cubes. If you are not planning anything crazy, you are good with any Long Tubes. Cat backs are a little more tricky, since Stainless Works connect to factory or the SW cat back. ARH connects to factory only, and kooks does corsa and factory. But with a little welding, anything can be made to fit together.

libertyforall1776

iTrader: (2)

^ Thanks! -- what about for the size of the full exhaust -- 2.5" or 3" -- that is the question -- any real gains to be had going over 2.5" w/headers & CAI?

ColeGraham

iTrader: (8)

Gains between the 2.5" and 3" cat back are not really there for guys that stay with our little ole 1.9L Eaton. The stock cat back is a 2.5", and flows very well. The only 3" cat back kit is through Stainless Works.

libertyforall1776

iTrader: (2)

^ Thanks, but it looks like some vendors are suggesting 3" (at least midsection), depending on mods:
http://www.redline-motorsports.net/s...adillac-cts-v/

ColeGraham

iTrader: (8)

3" mid section is your mid pipes...all the long tubes for 2009+ Vs have 3" collectors with either 1 7/8" or 2" primary. And the mids will taper to a 2.5 to connect to either factory or after market cat back. Stainless works is the only cat back kit to offer a full 3" cat back. Which is why you chose the mid (or connector) pipes to go to either Factory or the Stainless works act back. There is dyno results all over the other forum, with guys that run the full 3" gaining maybe 5 to 10 over a 2.5" cat back.

Hell, there are guys making over 600 at the tires through completely stock exhaust, and without spray.

libertyforall1776

iTrader: (2)

^ Thanks for your tips, it's been helpful... More research needed at the other site though.

DACTARI

iTrader: (1)

If you're staying close to stock on the motor, the cat back is really a sound mod. You may have enough with headers and e-cutouts, which can be opened incrementally to give degrees of sound, or closed completely for whe. You want to sneak around.

ColeGraham

iTrader: (8)

Truth. After talking to my tuner/builder...I went with American Racing, since I am saying stock cubes and stock Eaton. The 2" into 3" that Stainless Works offers would be way overkill, plus stock displacement and blower would not be able to take full advantage of that much flow.

Cut outs will hopefully go on before I head west...love the ideal of being obnoxious on demand.