TX Tahoe Z71

iTrader: (28)

I am wondering how the stock exhaust piping is on a 2003 Tahoe 5.3, because I was thinking of just replacing the stock muffler with a Borla Pro XS. How much horsepower would I leave on the table by not going with a custom mandrel bent cat back single 3" (assuming it would fit) with the Borla muffler? I want something that is quiet and not flashy (ie big chrome tips). Also, is there a muffler out there that would be quieter than the Borla with the same hp gains? Any input helps. Thanks.

gonzo 6.2

iTrader: (8)

Almost any aftermarket muffler is going to be noisy and have some drone and little seat of the pants feel and it's possible to loose botton end feel.Do yourself a favor and have a custom tune done first with a Nelsons or a westers,Now you have something that feels tangible.After all the muffler swaps I have done the HD flo-pro flows well and has minimal drone.

therock

iTrader: (2)

I will be putting it on soon and report here in a new thread. I got the "Touring" edition, the quieter of the two, the "Sport" being the louder one. It is a far cry in price from just a muffler, but it is supposed to be dead silent in the cab and has a straight through flow design.
We will see.

CHAGO

iTrader: (1)

I'm still waiting on my Corsa to come in

TX Tahoe Z71

iTrader: (28)

I am planning on getting a Nelson tune shortly. So far I just have Volant intake, but that alone made a huge difference; I picked up a lot of low end and part-throttle acceleration. About the muffler, I just assumed that since the stock one is almost 3 feet long that it was very restrictive. What would I expect to gain with just a Borla muffler swap? And where can I find an HD flo-pro?

TX Tahoe Z71

iTrader: (28)

I just climbed under my truck and found out that the stock exhaust is a single 2.5" in and dual 2.5" out that merge back into to a single pipe. Assuming I just replace the muffler, would I want to go with that setup, or just do a single in, single out 2.5"?

therock

iTrader: (2)

First, the mufflers on our NBS trucks and Tahoes are 24" long and the Tahoes and Suburbans are like the SS Silverado in having a dual outlet that is really only one. Don't ask me why, I have seen them cut open and only one of the Y-outlets flow.

badpewter-z

iTrader: (4)

they "extra" y section i belive is just for noise and resonence from what ive read.
you can easily just and a muffler to you setup and wouldnt really gain anything noticable from the complete catback on a stock motor. plus keep your stock look

greentahoe

iTrader: (2)

If I had it to do over I would have gotten some nice headers and a cutout. Catbacks and mufflers are a waste IMO. Im talking HP per $ of course.

TX Tahoe Z71

iTrader: (28)

I agree. From what I can tell looking under the truck, GM did a pretty good job with the piping (no severe crimping or bends), so I figure why spend $800 on a Corsa when an $150 muffler will get almost the same results.