Rasp Thread
Rasp Thread Well I just finished installing my set of XS LT's and ORY on a stock SS exhaust. My rasp worries were verified. When I'm just crusing and shifting around 3000 rpm, no rasp whatsoever, and I love the way it sounds. It's when I'm in a hard accleration and shift the rasp is HORRIBLE during deceleration of the engine rpm's. It's something I'm not used to. I don't want to put CATS on it, but I have plans to change the stock system out. Any other ideas to eliminate/reduce the amount of rasp I'm getting?
If you can, if people that had rasp and then eliminated it can post what they corrected on their system.
Thanks
If you can, if people that had rasp and then eliminated it can post what they corrected on their system.
Thanks
Originally Posted by STRIPSTAR
Acording to Pat G a very good 4" ymerge instead of a cheap ypipe removes most of rasp. Duels with good mufflers or as said - cats
I run a set of Dynatech Stainless with their pipe and high flow cats to a Corsa, no rasp, pops, hisses or anything. Its not a 4" merge but a quality y pipe none the less.
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good y-pipe, cats (only reduces dB but it helps with smell too), real mufflers...
bullets don't don much at all for rasp if they are straight thru ones. you need some kind of material in the way to cut the sound down.
bullets don't don much at all for rasp if they are straight thru ones. you need some kind of material in the way to cut the sound down.
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From my understanding, what happens is that the air bounces back and forth in the I-pipe and that is what makes the rasp. The power pack muffler is supposed to make the air spin and control the air. Thus eleminating the rasp. I am gonna get one for my car when I can afford it lol.
Originally Posted by 2002_z28_m6
I have a hooker catback and american racing LT headers with a catted Y. There is no rasp period with that system atleast not on my car.
Originally Posted by STRIPSTAR
its the cats the help the rasp. I have a kooks ORY which is considered good but you still get rasp. The merge y-s are a different design that doesnt crash the exhaust into one pipe hence the noise.
Correct
https://ls1tech.com/forums/generation-iii-external-engine/761312-need-quiet-exhaust-cackle.html
I forgot I had this thread saved in my favorites
I forgot I had this thread saved in my favorites
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Joined: Nov 2003
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From: MD
If what you're hearing is the BLAAAAAAAh WHEN decellerating that is not rasp and is very common in a free flowing exhaust. It's just the exhaust depressurizing. Better y-pipes, bullets, etc.will help but you'll still get the sound.
I always had an annoying rasp problem when I ran a Y pipe setup. I tried several different mufflers, high flow cats, adding a bullet in the I then going into a single in dual out muffler...nothing worked. Still had that yawning cat noise in the mid 2000 RPM range and the nasty WOT sound
I cured mine by switching to true duals
I cured mine by switching to true duals
Originally Posted by Strahley
I always had an annoying rasp problem when I ran a Y pipe setup. I tried several different mufflers, high flow cats, adding a bullet in the I then going into a single in dual out muffler...nothing worked. Still had that yawning cat noise in the mid 2000 RPM range and the nasty WOT sound
I cured mine by switching to true duals
I cured mine by switching to true duals
Are you serious?!? True duals have so much rasp lol. Well atleast mine did with bullet mufflers and dumped at the axle.
Joined: Nov 2003
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From: Wichita KS / Rancho San Diego
I did the same install as the OP with my GMMG on the car and the rasp was like a jackhammer. I switched to a Hooker and still had rasp, but it was quieter. Then I went to custom Y with cats and Flowmaster merge. No rasp but way too quiet. Swapped my GMMG on and got some rasp back. Finally, I put a powerpack in the I and that took 95% of the rasp away with good sound. So for me, cats, FM merge, and powerpack solved it.
Don't assume that true duals will be an automatic solution to rasp. A friend put them on and the rasp was horrible. He went back to a Y.
Don't assume that true duals will be an automatic solution to rasp. A friend put them on and the rasp was horrible. He went back to a Y.
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From: Bensalem, Pa, now montreal, Quebec
i don't get how you have rasp with a stock exhaust. I have a stock exhaust with a dual/dual muffler welded in and i have zero rasp, but stock like sound. Its whisper quiet like a stock z28.
[you regulars will understand] 