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Exhaust concerns

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Old Sep 18, 2009 | 07:19 PM
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Default Exhaust concerns

Hi guys, new member here. Just picked up a white '06 Impala SS as my daily driver. I've been in trucks and SUVs for the last five years. Thought it was time to get back into a car. Love the Impala. I work on cars and have driven the V8 Montes and Impalas before, so I went searching and found one. Anyway, my question is, have any of you guys had any kind of loss of power when changing exhaust systems? I had an '06 Trailblazer SS with the 395 HP 6.0 and I had a custom bent 2.5" stainless sytem built for it with a flowmaster super 44 series muffler. It was 3" in and dual 2.5" out. After the exhaust was installed, I noticed a loss of power...as if it wasn't using all of it's potential like it did with the stock exhaust. I'm not looking to shave a second off my 1/4 mile or anything, but I don't want to run into the same problem if I throw a couple of flowmasters and some stainless tubes under the car. Any of you guys experienced this with the Impalas, Montes, or GPs?
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Old Sep 18, 2009 | 07:29 PM
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First off welcome aboard... When you say you lost power I assume you mean on take off. I am sure that truck was way faster in the upper rpms?

When I first got my GXP I wanted it to sound better so I took off the resonator. It sounded great and no power loss at all. After that I installed a catless 3" downpipe into the stock Y and mufflers. I have that current set up and did notice my car doesn't take off as quick as before BUT once she hits 2000 - redline it is a beast. So a larger downpipe puts the power farther up in the rpm range and it is worth it. Having had both I like the way the car is much better now. Very , very happy.

-Mike
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Old Sep 19, 2009 | 05:02 AM
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Thanx for the welcome. Actually, I noticed the power loss throughout the power band with that truck. Although, I didn't tune the computer after I installed the exhaust. And those trucks are designed with a single 3" exhaust system exiting on the right side only. I was wondering if maybe I opened it up too much after splitting the exhaust after the muffler into dual 2.5" pipes. Loss of back pressure maybe? The Impala is set-up the way it should be with dual outlets and dual mufflers...maybe that will make a difference and I won't lose the power like I did in the TBSS. I've got to do something with it, I can't stand driving a V8 and not being able to hear it! What do you guys think about a resonator delete, 2.5" stainless pipes, dual Flowmaster Super 40 mufflers, and 3.5" double walled tips? Mmm...sounds good already.
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Old Sep 19, 2009 | 07:44 AM
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everything you said sounds good minus the 3.5 inch tips. im not a big fan of big tips. But your last vehicle was a truck so i understand

Edit: I personally installed Thrush turbos with stock tips. so nowon knows where this noise is coming from hehe
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Old Sep 19, 2009 | 10:35 AM
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Well, the reason I thought about the 3.5" tips was because the stock tips are 3" across...so you'd only be talking another 1/2" bigger to better fill up the tip notches in the bumper. Plus, if they are double walled, they won't look as big as they are. I'll have to find a picture and post it.
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Old Sep 19, 2009 | 11:24 AM
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I can see why if there double walled they wouldnt look so big. I just think ricer exhaust whenever i here anything over 3 inches. How big is the stockers on my gxp? hmmm.
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Old Sep 20, 2009 | 06:32 AM
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The GXPs have dual tips, right? I haven't seen one recently and I haven't really paid much attention to how big they are. But, believe me...I will do my exhaust tastefully and stay away from the ricer look at all costs. I like a nice simple clean look and that's what I am goin for. Here's a pic of my TBSS that I had with the exhaust set-up to get an idea of how I like to have it. Those tips were 3.5"x4.5". The Impala tips will have to be round vs. oval because of the exhaust cutouts in the bumper, but you get the idea...
Attached Thumbnails Exhaust concerns-everything-5-9-09-016.jpg  
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Old Sep 20, 2009 | 07:29 AM
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Nice pic. Looks really nice. Ditch the resonator and then go from there.

-Mike
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