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Discussion Starter · #1 ·
Ok so i have a question. For those of you that don't know, I have the RS 2.2 shorty header, LSJ DP and a corsa sport catback. Now when i first start the car, it sounds fine at idol, but has a pretty bad rasp if i get on it. But after it warms up, the rasp completely goes away.. Is it just because of the aluminum block or is the cat maybe going out?
 

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It could be any number of things but if you cat isnt about 10 years old or a VERY cheaply made piece of junk then thats not it. The question is do you let your car warm up without just taking off when you jump in that creates a lot of friction on your engine because the oil is settled and cold also your pipes will go from cold to hot very quickly essentially causing fast wear on your car if you do it a lot and you car is older. Or you might have a bad gasket somwhere in the piping and when the pipe gets hot and expands it closes a small hole somewhere.
 

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Discussion Starter · #3 ·
It could be any number of things but if you cat isnt about 10 years old or a VERY cheaply made piece of junk then thats not it. The question is do you let your car warm up without just taking off when you jump in that creates a lot of friction on your engine because the oil is settled and cold also your pipes will go from cold to hot very quickly essentially causing fast wear on your car if you do it a lot and you car is older. Or you might have a bad gasket somwhere in the piping and when the pipe gets hot and expands it closes a small hole somewhere.
I do let it idol for about 15-20 seconds in the summer. in the winter, i usually don't leave until the temp says 80*

Now that you mention it, my DP to catback gasket is pretty rough. I have had it on and off about 4-5 times.. maybe thats my issue
 

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Discussion Starter · #5 ·
Yeah.. I have been meaning to, but haven't gotten around to it.
 

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ya that would make sense why its doing it... luckily gaskets are cheap
 

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Discussion Starter · #8 ·
I doubt the dealership has a 2.5 inch gasket for me though.. anyone know where i could get one online? I'll probably just go to an exhaust shop and pick one up
 

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it's cause the vehicle is still cold and not at operating tempratures... my 05 andd 07 both did the same thing.
 

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Discussion Starter · #10 ·
That makes sense.. It has always done it.. its just more noticeable with a the header and DP
 

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That makes sense.. It has always done it.. its just more noticeable with a the header and DP
yup that's because of the increased air flow now... pushin more thru.. it's like bein in band the more air you push thru the instrument the louder it plays... same concept
 

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if its anything like what I'm imagining there is still something off... it shouldn't make a raspy noise
 

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Discussion Starter · #13 ·
Well like i said, once it warms up there is no rasp what so ever!
 

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do you have a resonator? I know it sounds out there but my old civic(no I wasn't a ricer) had a wierd raspy kinda noise and it was that my resonator was f***ed.
 

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resonators do help with tone... but will still rasp a lil bit... and they blow out easily.. i mean i'm runnin absolutley nothing just a tip no cat no resonator for me...
 

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don't think u got what i meant... Ive never heard this raspy noise you're talking about so I'm just going off what Ive heard. If u have a resonator, give it somewhat gentle tap and see if it makes any odd noises
 

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if you have an aftermarket exhuast as soon as you start pull out on the road and put the pedal to the floor and it'll rasp until it get's to operating tempratures
 

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Discussion Starter · #18 ·
I don't have a resonator anymore. A weld broke on the inside of it and it was making an annoying rattle sound. So i just cut it out and had a straight pipe welded in its place.
 

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if you have an aftermarket exhuast as soon as you start pull out on the road and put the pedal to the floor and it'll rasp until it get's to operating tempratures
mine never have...
 
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