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Think I will get a little more power if I do this to exhaust?

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Old 10-23-2017, 04:28 PM
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Default Think I will get a little more power if I do this to exhaust?

So 5-6 years ago when I was young and dumb I bought everything for true dual 3" exhaust for my 5.3L after the longtubes. I thought bigger was better. If I could do it again I would have gone 2.5" on everything, but seeing as I don't want to re buy the whole exhaust......

current exhaust
LT 3" collector
3" highflow cats
3" magnaflow Xpipe - under front passenger seat
2-3"cutouts right after the X pipe - I mainly leave open
22" dual inlet/outlet magnaflow with x pipe built in. Dumped before axle.

Was thinking about buying a 3" y pipe and running one 3" cutout and getting a single 3" muffler. like borla xr1 maybe. Maybe have the y pipe right after the X pipe or 1-2 feet down from it.

What is yalls thoughts? Think it would maybe gain a little lowend back?
Old 10-23-2017, 04:32 PM
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Idle launch video
Old 10-23-2017, 04:49 PM
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Honestly speaking, I do not see it making much difference one way of the other. I dropped my 5.7 back to dual 2.5" from dual 3" factory exhaust piping and saw nearly no difference. The factory 4.8 Express vans had dual 3" pipes off the manifolds to the dual cats to the muffler and run just fine. When I had my 5.7 Hemi Ram it was noticeably quicker at the track with a 18" piece of 3" pipe after each header collector with a turndown on the ends than it was with a full 2.5" dual exhaust.
Old 10-23-2017, 05:03 PM
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Yea part of the reason I'm considering the change is b/c I want to move the cutouts from under the cab to the bed, but I have a two piece drive shaft so the cross member is in the way and no room with the 22" magnaflow. So only way to do it is to get like a 14 or16" muffler to allow room to move the cutouts back.

I also wonder if having the cutouts right after the X pipe Kinda defeats the purpose of the X pipe.
Old 10-23-2017, 05:05 PM
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I wouldn't bother changing it unless you hate the way the current setup sounds. A 2.5" dual setup probably would have been sufficient for a 5.3, but a 3" isn't hurting you at all unless you really want to reduce weight. That's the only thing you'd gain (or lose) by switching to a y-pipe with a dumped single muffler as opposed to a full true dual 3" exhaust.

Old 10-23-2017, 05:05 PM
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This video kinda shows where everything is at
Old 10-23-2017, 05:19 PM
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Originally Posted by BudRacing
I wouldn't bother changing it unless you hate the way the current setup sounds. A 2.5" dual setup probably would have been sufficient for a 5.3, but a 3" isn't hurting you at all unless you really want to reduce weight. That's the only thing you'd gain (or lose) by switching to a y-pipe with a dumped single muffler as opposed to a full true dual 3" exhaust.

https://www.youtube.com/watch?v=_PVX...t5dIHutSOu7srE
several years ago with stock cam I dynoed tuned it with shorty headers stock cats and dual 2.25" exhaust and 2.25" cutouts in the same spot. When I went to the LT, high flow cats, xpipe, and 3" exhaust with cutouts it gained 14rwhp and 11rwtq still on stock cam. Told me the shorties probably only gain 10ish where the longtubes gain 20-25ish



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