Exhaust Mods
#1
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Exhaust Mods
I currently have GT500 axlebacks on my 2012 GT. I'm considering putting a new H-pipe (which will use the stock cats) in to get a better sound. I know that the bigger diameter of the pipe should allow for better exhaust flow. In order to make that better exhaust flow useful, do I need to remove my resonators as well? Is it worth it if I'm not removing the cats?
#2
Bullitt Member
I would remove the resonators. The stock H pipe is very restrictive, like 2" or 2.25" and the restriction doesn't end until after the resonators. I did a 3" Pypes X pipe and 3" tubing back eliminating the resonators and it really woke up my GT500 mufflers.
#3
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Good question. Removing the resonators will make it a little louder for sure, (there's a few videos around to demonstrate that), but I'm doubtful you'd see more power with the stock cats still being the major restriction.
An after-cat X-pipe is supposed to be worth maybe 3-4hp. Now how much of that is because it's a more efficient X, or because it eliminates the restricted section of the stock H?
I'd like to change out the mid and over axle pipes too, just because it bothers me knowing those reduced diameter sections are there. In reality though, the power they rob on a near stock car with the factory cats is probably negligible.
I doubt you'd be able to hear a difference just changing to a larger H section either.
Just my thoughts, no real experience to confirm.
An after-cat X-pipe is supposed to be worth maybe 3-4hp. Now how much of that is because it's a more efficient X, or because it eliminates the restricted section of the stock H?
I'd like to change out the mid and over axle pipes too, just because it bothers me knowing those reduced diameter sections are there. In reality though, the power they rob on a near stock car with the factory cats is probably negligible.
I doubt you'd be able to hear a difference just changing to a larger H section either.
Just my thoughts, no real experience to confirm.
#8
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Originally Posted by 11SHELBYGT500
You crazy, this is the most fun state in the union.
#9
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Did you keep your cats or what are you doing for emissions tests?
#10
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My cats are still there. I live in one of the two countys in Arizona that require emissions testing, but they only do an OBD compliance check so as long as I don't change anything to mess that up I'm good.
#11
Bullitt Member
I'd like to hear your set up too. Do you hang with one of the local mustang clubs? There are a couple here and at least one does regular get togethers. I live west side.
On another note, I saw a clip of Heartthrob exhaust and they were claiming 4 hp from an x pipe cat back but 20+ from an h pipe cat back...Intresting...
On another note, I saw a clip of Heartthrob exhaust and they were claiming 4 hp from an x pipe cat back but 20+ from an h pipe cat back...Intresting...
#13
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Right? I have an axleback and i'm basically at the limit of exhaust mods.
#14
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I havent had time to hang out with the clubs down here. I would like to tho. I live on carefree and i17. I will be more west in a few weeks when my house is done (El Mirage Rd & 303).
#16
#20
Bullitt Member
You have an axle back if you change the mufflers. If you replace pipe from the cats all the way back to the end of the resonators, you would have a cat back system with the new mufflers. Your choice as to X or H for the mid pipe, and use at the least a 2.75 inch diameter pipe.