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Hi All,

Was going to post a seperate thread but I thought posting in this one would be appropriate!

It's time to get a new exhaust/muffler for my R33 RB25DE GTS4..

Currently it has a Genie tri-flow/reverse-flow ('turbo' style) muffler, 2 resonators and 2.5" mild steel piping for the straight section, then it steps up with a bolted flange to 3" at the bends (I got it off a mate who changed his muffler on his gtst, which was 3") trumpet style, haha. Muffler has a loose baffle now and sounds crap, and i'm sick of the drone. The ideal new setup would flow a bit more freely than the stock system (of course keeping sufficient back pressure), don't want to any drone at 100KM/H, however when on the pedal a little bit louder than stock would be good. But not something that will attract the police, etc.

So I'm after a new muffler/fitting. Can anyone recommend what mufflers are good for this job? are an exhaust shop in the city/surrounding suburbs area that can do it? Prices?

cheers,

chicane

Okay, just to clear up something fer me...

If I just want to give the car a slightly louder/gruntier sound than stock while idling and accelerating can I just buy a larger exhaust tip, or would I need to get a muffler aswell?

I just wanna get that deep growling sound :wassup:

one other thing, my car has a turbo (bone stock Gts25-t) if I do decide to go with a muffler aswell what is the optimum size piping for it?

dumb questions I know but keep in mind I know nothing about exhaust systems

  • 3 weeks later...

Hey guys just letting you know i got my exhaust fixed the other day, and yes Eug you were right it was the resonator. They fitted a larger one and it has completely eliminated that annoying rasping note! Sounds mad now a really deep throaty note. So if anyone has that prob which i know a few of you do, change your resonator or put one in! :P

  • 4 weeks later...
http://fujitsub.rsjp.net/search/prod-v.php...cnamID=00000523

it's 2.75" piping. What do you guys reckon?

hey davor,

2.75" will be very droany on an NA

i personally wouldn't go over 2.5" (i can remember by old 3L NA supra that has 2.5" and itself was very droany when cruising - annoyed all my passengers)

i think the secret is to have as large a resonator as you can to keep the droan down but keep the flow and exhaust note

:D

miscommunication possibly?

by tip i mean muffler... not just ricey chrome metal wrapped around teh exhaust.

a mate has fitted his civic with a tip (muffler) whatever u want to call it. and it has changed the sound.

tip ie. the tip that sticks out.. muffler cannon... whatever

thats how everyone else have been referring it to in this thread.

if not my bad and i am confused and got no idea what ur on abt

:)

Misunderstanding of basic terminology on your behalf perhaps.. Never have i heard a 'tip' being the muffler.. :confused:

ok people this thread has gotten way off track - it seems that some backpressure is good with NA engines, and it seems that 2.5" diameter piping is ideal as well.. lets get some actual useful knowledge in this now!

What mufflers are a good choice? If you have got an NA skyline, and have an aftermarket exhaust, post up what muffler you have (its specs as well if possible) and what you think of it...

cheers :rofl:

i got a 2.5inch magna flow cat back. one resonator. 2.5inch inlet with twin 4inch tips. Looks the sh1t and sounds even better. Made a minor improvement in performance. CAI made a better difference. Cant wait til i get extractors but that aint gonna happen til a group buy takes off.

Please stop saying you need some back pressure on the exhaust of NA engines... As was mentioned earlier you don't need any back pressure, as this is just wasted energy, what you actually want is a small enough pipe to allow exhaust scanvenging.

This is where the momentum of the flow of exhaust gas in the exhaust effectively helps suck the gases out of the cylinders. This is of benefit at lower RPM where the volumetric efficiency of the engine is low.

Putting a bigger pipe will help peak power at higher RPM where volumetric effieciency is higher but at lower RPm you will loose out and have a less driveable engine. Again as has been said there is a big difference between a drivable engine that feels fast and strong and one which makes a higher number on a dyno.

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