SVT THIS

iTrader: (27)

I had a guy I know install my SLP LT headers and SLP ORY. For a while I drove around with an open cutout on my stock catback. However, the rasp was pretty bad so I decided to close it up. I realized the rasp was not from the open cutout. It sounds like a metallic tap/cling coming from under the center console. Is there anyway that my headers or ORY could be installed incorrectly? What could be banging around down there? When I am idling it is not there, however, if I let the rpms get above 2k (which they do quite often with my stall) I can hear it. It seriously sounds broken. I don't work until later tomorrow afternoon so I am hoping to get under there and see if something is loose. I need you all to tell me what to look for! Thanks

TheBlurLS1

iTrader: (8)

Loose clamp or it's hitting the body somewhere. Look for marks where it sits closest.

BigDaddyBry

iTrader: (15)

Double check the clearance and re-tighten the clamps while its still hot/warm.

I've always thought rasp wasn't so much a function or fault of the muffler but more due to the vibrations in the exhaust system.

SVT THIS

iTrader: (27)

Thanks, I'll let you know how it goes tomorrow.

SVT THIS

iTrader: (27)

Ok guys I jacked up the car and got under her for a while. I tightened up all the flange bolts-they were already pretty tight but I tightened them till they wouldn't budge. Then, I noticed a mount with the word "auto" on it connecting to the y-pipe. I assume this is the tranny mount. Anyways, the only bolt connecting to the Y and the mount was VERY loose and I could not tighten it (stripped nut). So, I dug around my garage and found a bolt and nut that was equal in size and put her in. I tightened it up as much as I could and tightened up my cutout bolts. I then checked around the headers and the Y for any contact between the piping and anything else. I didn't see anything.

I took her off the stands and drove her around the block. It no longer sounds like something is broken it just has that "beans rattling in a can" rasp to it. I have no carpet so it is probably a little worse than your average in car rasp. My temporary solution-drive around with an open cutout. I won't hear the rasp over the exhaust drone (anyone can appreciate drone over rasp, right??) and my neighbors will just have to deal with it.

So, what should I do to solve the rasp? I am going to go up to my exhaust guy tomorrow and see how much he could do a custom true dual setup for. Would an H-pipe or an X-pipe be better? I will run it over the axle and out the back through my flowmaster right now then out through the CME. I will have cutouts on both pipes for the track and Friday nights. Should this solve the rasp or will I always hear it no matter how much I spend on my exhaust? Thanks

litemup02

iTrader: (39)

Yeah i'm going with the duals soon too. that rasp is driving me nuts...sounds like an old truck. From what i hear on ls1sounds.com the duals sound ALOT better. Sounds like the X-pipe is the way to go---good luck

BigDaddyBry

iTrader: (15)

Poly motor mounts are another option. It got rid of the ocassional rasp I would get. But if you can't do them yourself, then the cost would be similar to TDs, and you'd get more enjoyment out of the TDs.

ChocoTaco369

put cats on that bitch! get rid of the rasp and raw exhaust odor. you won't lose enough hp to even notice it. if you do, it's likely in your head just make sure you get a good set of high-flows.

true duals are nice too. cats are just oh so much cheaper

radz282003

iTrader: (1)

Ditto the cats'.

Shigma2k2

iTrader: (3)

I'm having the same sort of rattle with my race qtp's, qtp ory, and magnaflow catback. I only get it at 2-3k rpm and everything was tightened down. It sounds like two little pieces of metal are clanking together. I put the end of screw driver to the ory to compare the vibes I felt to the vibes I heard and they didn't really coincide. Is this normal without cats, is it just rasp? What RPM range is rasp heard, throughout or just at little resonance points?

SVT THIS

iTrader: (27)

Why would the rasp be there without cats but be gone when you install cats? Would running a cat-less true dual setup eliminate the rasp or should I run high flow cats in the TD setup?

HD1911

iTrader: (13)

**** cats...i hate em

BigDaddyBry

iTrader: (15)

I would speculate that it has to do with disrupting the exhaust flow enough to change the resonance. I see the exhaust flowing in such a way as to cause a vibration in the system that results in it resonanating and creating rasp. When cats are used, you change the flow slightly.