SliverSS

Did a search, found some stuff but nothing really helpful!

My car sounds like it has a sore throat, and can't be cleared...When accelerating the note from the exhaust sounds like "rapping" Almost like air being forced though a flapping valve...

I have FLP headers, ORY, Loudmouth. I don't think it's the typical rasp, because the sound has changed recently...

Also, if I let off of it at like 5k and let it engine brake...the exhaust will get way louder halfway through coming back down the RPM range...it's very odd.

I haven't felt any air leaks (from the part of the header I can get to from up top)...are there any other signs I could look for? Does that sound like a header/exhaust leak?

BTW, the car is blown and the air system has been removed

WILWAXU

iTrader: (6)

Are you sure it's not your blow off valve?

SliverSS

yeah positive...it's coming from the exhaust.

From what I gather it could be 2 things...bent push rod or a header leak. I guess I'll put my stock gaskets in and see how that works (i need to buy some stage 8 header bolts/air tube gaskets anyway)

CCSRACER

Ever figure out what the problem was? I have the exact same problem. I replaced the header gasket and it still has a distinct tapping coming from the header/valve cover area when on the gas pretty good. I don't hear it when I accelerating very, very slowly, only when Im maybe 1/4 into the throttle. Anyone have any ideas?

Z28Venom

iTrader: (13)

I believe what you're describing is RASP.

You get this when you run the SLP Loudmouth exhaust with LTs and an ORY.

A few things to help you out:
- switch to a catted y-pipe
- replace resonator in LM w/ Borla XR-1 (40085)
- dump the Loudmouth for a less annoying exhaust
- Hooker
- Magnaflow

Or you can ditch the y-pipe catback setup all together and go TDs.

CCSRACER

Its definately not rasp. I actually never had this sound until had cats welded into my ory (this past saturday).