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      04-22-2010, 08:43 PM   #1
MrHarris
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Exhaust buzzing sound

I just installed my Dinan mufflers, and everything's great but I seem to have this metallic buzzing sound right at around 2500rpm.

I thought it could be due to the muffler cans hitting the heatshield but there is plently of clearance all around.

I've had this sound with my Gintani race and my Remus sport. Both of those were also only at a certain RPM.


Anyone have any idea if this is normal or if there's a fix? Maybe the exhaust is hitting touching something that I overlooked?
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      04-22-2010, 11:46 PM   #2
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If you checked all bolts and fasteners, it's going to be one of two things: internal rattling (manufacturing defect), or most likely, the resonance is making something else rattle. And most likely it's the heat shield somewhere. You'd have to get under there and touch the heatshield all over the place and see if it touches metal easily, and you can bend it back a little more to create a bigger gap. That's one of the drawbacks of an aftermarket exhaust. And you happen to have one of the quietest on the market. Oh, I'd also check that the safety straps (if you reinstalled them) are not touching anything. Good luck.
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      04-23-2010, 01:31 AM   #3
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Quote:
Originally Posted by elp_jc View Post
If you checked all bolts and fasteners, it's going to be one of two things: internal rattling (manufacturing defect), or most likely, the resonance is making something else rattle. And most likely it's the heat shield somewhere. You'd have to get under there and touch the heatshield all over the place and see if it touches metal easily, and you can bend it back a little more to create a bigger gap. That's one of the drawbacks of an aftermarket exhaust. And you happen to have one of the quietest on the market. Oh, I'd also check that the safety straps (if you reinstalled them) are not touching anything. Good luck.
I looked at the safety strap. It seems like it has to to touch something? I wouldn't think a strap would rattle?

I'm 95% sure my exhaust is not touching the heatshield, cold or hot. All bolts are tightened... I do know my strap is touching stuff... I guess I'll fiddle with that.


Our cars aren't known to make any weird metallic/rattling sounds under 3k right? Just an exhaust install complication?
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      04-25-2010, 12:00 AM   #4
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Quote:
Originally Posted by MrHarris View Post
I looked at the safety strap. It seems like it has to to touch something? I wouldn't think a strap would rattle?

I'm 95% sure my exhaust is not touching the heatshield, cold or hot. All bolts are tightened... I do know my strap is touching stuff... I guess I'll fiddle with that.


Our cars aren't known to make any weird metallic/rattling sounds under 3k right? Just an exhaust install complication?
I had it with fabspeed X pipe. Started after it heated up and was touching. If it's a metallic buzzing sound, it's definately a high frequency rattle caused by resonance where it's touching.

Put the car up on a lift and go though it again.

You enjoying the Dinan? What's that, your 8th system lol
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      04-25-2010, 12:32 AM   #5
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Quote:
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I'm 95% sure my exhaust is not touching the heatshield, cold or hot.
It doesn't have to be touching it buddy. Remember resonance rattle things not even close to your car .

I suggest you put your car on ramps, start it one morning (when it's the roughest), and get on your back right away to investigate. If the heatshield doesn't have a healthy gap from other panels, that can be your problem. I agree the strap is not going to rattle much; just make sure it's not coiled or touching anything. Push the heatshield lightly with your fingers all over, and if it touches anything, pull it a little bit to create a bigger gap. Good luck, and hope you find the culprit. Keep us posted.
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