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Just wondering if its natural for stock n/a 33 to have a rattly muffler??

also, what should i look for when purchasing one?

that sounds a little like what my car does, a rattle noise happens when i get up in the revs and i thought it was just my stock exhaust system but i now have a new one and it still happens, now that im thinking of it i think it goes away after driving for a while and getting the car warm. i would also be interested what this sound is and how i can get rid of it.

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The rattle in your exhaust you will find is probably the catalyic converter, the honey comb-like inside has probably came loose, un do that and have a look inside, if its that, bash it out and replace it with a new catalyic as soon as possible.

Hope this helps mate.

Dayne

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If a muffler is faulty you can tell by stabbing at the throttle at idle and then quickly taking your foot off. If it makes a rattling/hissing noise then either you muffler or catalitic convertor is loose or faulty. Another way to check this is to get under the car and hit it with your fist. If it's a solid noise then its fine other if it makes a rattling noise there is your problem.

Eli, is your exhaust a cat back exhaust? The dump pipe to the cat convertor is protected by a heat shield which encases the pipe inside. They can come loose and rattle but will only make a noise in the case of idling normally. A couple of ordinary hose clamps wrapped tightly around the heat shield should fix that. If any of those things dont help then its not your exhaust system.

Hope that helps.

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yeah, I done a search after i posted :) ....

the thing is, there seems to be more than 1 solution to fixing it...

I just purchased one with a rattly exhaust (1st oz owner) and the guy told me it happens on all n/a r33s and can be fixed with an aftermarket exhaust...i was wondering if he was b/s'ing me....it doesnt rattle whilst idling though ...anyway..thanks

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it does happen to all of them and its almost never something rattling. Its resonance in the exhaust system that becomes more pronounced as the packing in your muffler gets old and the cat deteriorates. Yes a well built aftermarket exhaust will fix it, if u take it to someone that doesnt know what they are doing it will just amplify it....

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Its resonance in the exhaust system

Its almost never something thats come loose.... resonance is something that twin cam engines do. Too hard to explain how it works but its that rattling sound u hear... u need an exhaust shop that knows what there doing or follow the write ups that are in this section of the forum.

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