Need Help!! Bad Exhaust Vibration - Hyundai Performance Forums

project_tiburon · 11-11-2003, 12:12 AM

I recently put a obx 4-1 header on my 97 tiburon. Not the dual y or whatever this is a real 4-1. And ever since then when i get to around 3 thousand rpm's it starts vibrating bad. After i get to around 3500 it quits. it sounds really bad ive been puting around lately so no one can't hear it. Ive read posts on here before about the catilatic converters messing up and making funny noises after a header in installed. I read one about pinging comming from it and all sorts of stuff/ They sent me the catilatic converter with it, but i think that maybe whats making the noise if it is. Does anyone know what exactly the vibrating noise might be and how to fix it. All responses are greatly appreciated. Thanx

tibby01 · 11-11-2003, 12:29 AM

you could try putting the old cat on and seeing if the vibration goes away then. make sure you torqued all of the bolts to the proper lbs./ft. too.

the header bolts need to be 32-37 lbs./ft. with the engine.

go here http://www.hmaservice.com/webtech/ if you need other torque specifications.

[Edited by tibby01 on Nov 10, 2003 8:30 PM]

Mad-Machine · 11-11-2003, 10:34 AM

Just remember.. a header is not as quiet as the stock exhaust.. there will be some places in the RPM band where you get resonation issues.. (I know you guys hate this) but even my fiat spider.. with NO cat.. came down with a slight resonation when I went to headers..

Random · 11-11-2003, 12:46 PM

exhaust resonation is a frequency/vibration thing. You need to figure out what part of the exhaust system is having the issue, then move/replace that part. The most common causes are "straight thru" mufflers with very thin walls, and cat converter heat shields. It is possible if your ehxaust was built/made with thin wall tubing that it is the actual exhaust piping itself resonating. The one way to tell for sure is to test. GO to an open parking lot, and have a friend rev the car to the offending RPM. Get a long block of wood, or a wooden dowel of at least 1" diameter. Then press the wooden dowel/block of wood against the exhaust system at various different points. When you find a point that dampens the vibration noise, you've found the problem.

project_tiburon · 11-12-2003, 01:15 AM

Alright thanx guys, i think im going to put the old cat back on and see what that does. If it dont work im going to take it to the exhaust shop and ask them about a straight pipe to replace the cat. Im in kentucky so they dont check nothin here for the cat. converters. For most people here it is a normal thing to take them off of a car when u buy them. I forgot to mention i also have a MBRP exhaust, so when it vibrates it is a deep vibration. VERY LOUD. So i really have to get something done with it. Thanx again

01IMPORTSHARK · 11-13-2003, 02:06 PM

hey man. i got the 4-1 OBX racing header too. what kind of vibration r u talking about? a crackly noise or a real vibration. when i purchased the header it came with a strait thru cat " test pipe" and i got a vibration with alot of crackling. i put the stock cat back on in place of the test pipe and got a magnaflow muffler and it now sounds like i have never heard before. it has a pretty deep sound that gets kinda high pitched w/ a lil whish sound from the cat.

01IMPORTSHARK · 11-13-2003, 02:07 PM

i also might recommend getting a resonator installed. some people like to use a cherry bomb or something alike for a resonator

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AUTOBOT · 11-13-2003, 03:13 PM

Quote:

Originally posted by project_tiburon
[body]
Alright thanx guys, i think im going to put the old cat back on and see what that does. If it dont work im going to take it to the exhaust shop and ask them about a straight pipe to replace the cat. Im in kentucky so they dont check nothin here for the cat. converters. For most people here it is a normal thing to take them off of a car when u buy them. I forgot to mention i also have a MBRP exhaust, so when it vibrates it is a deep vibration. VERY LOUD. So i really have to get something done with it. Thanx again
[/body]

I don't get it, somebody (Random) gives you a sure fire way to figure out exactly what the problem is for free and yet you still insist on ripping parts off and paying to have others replaced without knowing what the true problem is.

Why did you even bother asking the question to begin with if you are not going to follow the advice given to you?

Mad-Machine · 11-13-2003, 05:26 PM

There is a term for that... MMTB.. More money than brains.

rockym20 · 11-13-2003, 06:43 PM

Na, he just doesn't have any friends

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