Bloody Exhaust!

[SKYLINED]

I posted this ages ago, but that horrible sound when the car hits about 3000rpm is frustrating!!!

A mechanic of mine seems to think that its the heat shielding thats making the vibrating noise.

Anybody have the same problem, but solve it?!?!

Thx

[paulr33]

what car/engine are you talking about? i had a friend with an rb30 vl commo and it basically vibrated a shit load when it got over about 80km/h and it was in high gear and running at about 2000rpm so he would have to run it it in power to kick the revs upto 3000 so it didnt make the noise. i believe the noise is purely ****ed exhaust. he insists on running it at 3000 (in power mode) all the time vs getting it checked/fixed

[Pva_Glue]

whats the noise sounds like?

more droning?

or

rattling?

[JAMESW]

I hate the noise my na r33 exhaust makes...

it was ok before but once i got he extracters fitted it now has pipe noise wich sounds shit.

James.

[Greg]

Its not the heat shield - I get the same noise but I have aftermarket extractors, no heat shield.

This came up before and I think the general consensus was that it was the cams.

I've actually grown to like it - tough, raspy N/A sound

[Ryno]

Get another resonator fitted to your exhaust, and it should solve the problem.

When my car was NA, I had two resonators and the rear muffler, it may sound like overkill, but the car sounded bloody smooth. When the extractors where fitted, it did sound a little "throatier", but you'd have to know the car pretty well to tell any difference.

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For sale: Cobe Extractors to Suit RB25/20DE - $200

[SKYLINED]

The car is a R33 rb25de

Hmmm, how hard is it to fit the resonator? i guess u'd have to cut the pipe to fit it in there.

Got any ideas on the money involved Ryno?

Attached is the exhaust note it is making.

[Ryno]

It's been a while since I've bought a resonator, but I'd be very surprised if it cost more than $200. As for fitting, they just cut out a section of your exhaust pipe and weld the resonator in place.

After listening to that attached flie, it sounds like a secondary vibration of some sort, and not the exhaust note. I'd have a good listen to find out where the noise is coming from, it maybe as easy as the exhaust bolts needing a tighten.

__________________________________________________

For sale: Cobe Extractors to Suit RB25/20DE - $200

[SKYLINED]

ok, ill have to get under the car and have a proper look and get another person to rev it.

Tell ya how i go

Cheers

[Greg]

be careful not to burn yourself!

check the heat shields surrounding you cat, a friend had a similar problem for a bit.

sorry i know i just contradicted myself, in my first post i was assuming that u meant the heat shield around the exhaust manifold

[pstanbis]

i recently had to have my resonator changed to get a sticker off - went from 3" hotdog to 2.5", large barrel muffler (stuck in the middle of the 3" piping) and it has a simmilar sound - just over 2750 rpm, it howls so sharply and for sucjh a short time, that i too thought it was a rattle, but when held on the revs, it still makes the noise - it rally pisses me off too... not that it wasn't loud before but at least it was constant... will change it all later, but thats another story (and thread)

good luck with getting rid of that noise mate, coz your right, its nasty !!

[geordie]

My exhaust history - standard exhaust had the very noise you are speaking of noise at 2800-3100rpm, but being stock was fairly quiet, then fitted rice cannon, which acted like a huge amplifier and the noise was massively loud , eventually i was pulled over and defected, went to the exhaust shop had a 2.5inch sytem fitted with the largest resonator they could fit, but keptthe cannon muffler, i now get a slightly hollow pipe noise but still sounds decent, the snappy high noise is there but much more muffled and contributes alot to the pipe noise. Personly, it scares ppl cause they think you have some crazy mods or something ???? but yeah, basicly...

Moral of the story - i think its something to do with the cams as mentioned above cause i cant get rid of it, muffle it as much as you can and live with it...sorry buddy

[NA_R33]

dude its called resnonance sp* all na rb25 have it as mentioned about its due to the degree of overlap in the cams, u cant get rid of it, only way i got my car to sound better was hollow cat and 2.5" straight through to a cannon, my exaust is still stting at home if u want it including a set of headers. Its very very hard to get rid of the noise without the car being loud, i tryed different exhaust shops and only fixed it when i started working at a performance shop.

[gts4_fun]

be4 i got my zorst redone it made a really shitty ratteling noise... i found out my cat was stuffed and i had stones cought in the heat shield, after got that all fixed up it was all good! dunno if this is ya prob but that's what i had...

[MirKz]

hrmm hopefully when i come to getting my exhaust system done it shouldnt make a wierd noise like that... HOPEFULLY.

I plan on getting brand new tuned length extractors, with a high flow cat and 2.5inch system (maybe all custom depending on funds)... and yeah a huge stainless muffler

[SKYLINED]

Thanks for all the info guys. I havent had a lot of time to attend to the problem due to being so busy. Will try to get to it soon.

[SKYLINED]

Ok, found last night there was a rust hole in the joining weld between the pipe and rear muffler. The noise is really loud when the exhaust is cold, but slightly got quieter when hot.

Trying to find a s/s muffler or cat back system 2.5".

If anyone has or can get it. let me know.

[White-R33]

a while ago, i had an exhuast system on the NA motor before i swapped over... 2.5 inch system.. the resenator/muffler had a lose baffle inside... it was making the noise at certain rpm's

maybe swap the resonator.. they dont cost much at all. cheap as chips in comparison to fitting new system.

[SRW-1]

Yeah mine's the same, at first i liked it but now it drives me crazy. It's a weird vibrating noice once it hits certain revs. What type of exhausts do you guys have?

[crayman]

I had the same problem, but removed my lower exhaust manifold heatsheild and it went away. Did it around 3000rpm too!