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Old Feb 3, 2012 | 04:25 PM
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Default Raspy 383

Right now I have a 383 with a 11.3cr, it has slp LT's, ORY, and borla, wt no block off plate..I like the fact that the car is loud, but hate the raspiness around 2000 rpms and when you get of the gas at high rpm..I dont want to change the whole set-up, thought about adding high flow cats, or flowmaster merge, and or just adding a bullet just before the axle..

..what have some of you guys used or done?, what really works to loss the rasp?
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Old Feb 3, 2012 | 06:36 PM
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The cats will definately knock the rasp out. I have a rumbler system on my car, when i pulled my cats off,,thats when I got the rasp i have now. I am in the same boat looking for something a little tamer at low rpms. But i will live with the rasp before i put cats back on.
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Old Feb 4, 2012 | 07:56 AM
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Originally Posted by RARON455
But i will live with the rasp before i put cats back on.
...was it to quiet with the cats installed?
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Old Feb 4, 2012 | 11:37 AM
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Remove Borla, replace with Mufflex cb w/ Magnaflow single in/out
Problem solved
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Old Feb 4, 2012 | 11:47 AM
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i have QTP long tubes, QTP y-pipe with the flowmaster4" merge, to a cut out and the Magnaflow single in duel out. i have no rasp what so ever. no cats. i used to have rasp with my SLP cat back but once i went with a real muffler, it went away. i also noticed i can run around the street with the cutout open and i still dont get any rasp
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Old Feb 4, 2012 | 07:21 PM
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Originally Posted by Justin Gibbons
Right now I have a 383 with a 11.3cr, it has slp LT's, ORY, and borla, wt no block off plate..I like the fact that the car is loud, but hate the raspiness around 2000 rpms and when you get of the gas at high rpm..I dont want to change the whole set-up, thought about adding high flow cats, or flowmaster merge, and or just adding a bullet just before the axle..

..what have some of you guys used or done?, what really works to loss the rasp?
Do something with these first. I had the EXACT same setup (b/o LS1 tho) and the rasp got to me after a while.

It's prolly behoove you to re-do the entire setup, but I understand if/why you won't.

I still have my SLP LT's and should be replaced soon. Adding a bullet muffler will help a little bit, but the resp is coming from the Y pipe itself. SLP's actually isn't a bad collector. If you add cats that will kill quite a bit of it, too. I had Random Tech cats on mine that came with the SLP LT's and I took them off after a while because I was curious. About 6 years later now and I'm about to put them back on to kill the rasp and shut the exhaust up a bit more.
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Old Feb 5, 2012 | 11:11 AM
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anyone know how much HP you would be giving up by going with high flow cats, and/or possible bullet in the I pipe?
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Old Feb 5, 2012 | 11:15 AM
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duals, no rasp period and will sound alot better
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Old Feb 5, 2012 | 11:21 AM
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i went through every catback, i wasnt happy with the overal sound, the duals are loud but honest the sound is so much better, and there was a for sure sotp fell over a y pipe setup, it depends what your looking for, loud,tame etc . if you like the borla i will say you will love duals, out of all the catbacks borla and gmmg was my fav, but the duals kick there *** in every way. i also liked the magnaflow catback but didnt sound mean ,had a good sound just wish it was a lil louder
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