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What's causing my raspy exhaust?

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Old May 17, 2015 | 02:55 PM
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Default What's causing my raspy exhaust?

On m rcsb it had a h/c lq9 and arh 1 7/8 lts, pry and a corsa muffler. On normal acceleration and wot it sounds great. But mid throttle it's crazy raspy. Sounds like a redneck straight piped ahit box.

With my xr1 it did the same thing too
If I open my electric cutout, the rasp is still there...

Is it the lack of cats causing the issue?

Add 2 high flows?

Thanks everyone
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Old May 17, 2015 | 03:00 PM
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yes, no cats adds more rasp
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Old May 17, 2015 | 03:00 PM
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The lack of cats is confounding the problem, however I had ARH 1 7/8 with catted Y pipe and Corsa touring catback and still had some rasp at WOT.
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Old May 17, 2015 | 03:29 PM
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Add a resonator.
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Old May 17, 2015 | 03:32 PM
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add a dynomax bullet to your I pipe. problem solved.
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Old May 17, 2015 | 04:03 PM
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Txsilverado, sounds like you speak from experience?
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Old May 17, 2015 | 04:18 PM
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if you understood exhaust design you would see why exhausts have rasp


any y pipe setup has rasp its just how much will you tolerate or cover up with muffler design

with said my truck has a 2.5'' y pipe into a 4" exhaust with a ultraflow muffler...raspy as all hell

added nothing more then a flowmaster and the amount of rasp went away

if you were able to have a true dual exhaust with exhaust tubing being identical like a new camaro or mustang or corvette the exhaust design takes away from the rasp

so for you OP you need to slow down the pulses enough to fix the rasp
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Old May 17, 2015 | 04:51 PM
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Originally Posted by bgray
Txsilverado, sounds like you speak from experience?
Yep. Longtubes with ory and corsa sport was raspy as ****! Added a bullet and fixed the problem. It did quieten down but corsa w longtubes and ory is way too loud anyways.
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Old May 17, 2015 | 08:11 PM
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Get rid of the Y pipe and run true duals. I had a Y pipe setup on my cammed lq9 setup and it was raspy, had the Y pipe cut, installed X pipe and 2 magnaflows and it just has a deep tone and no rasp.
Same scenario with my old TBSS
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Old May 17, 2015 | 09:22 PM
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Unfortunately I don't have much room to run duals and a x pipe, trucks 5/8 drop, single 3" is all the room I have with the bed supports cut.

Imma try a dynamat bullet, see how that works
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