Quieten Down A Performance Exhaust

[SECURITY]

I've got a pretty droney exhaust fitted but i want to quieten it down a fair bit. i'm not looking to make it completely silent but at least tolerable for daily driving. i've done a bit of searching and so far i've seen a lot of people say resonators are crap and only some mid-mufflers work.

does anyone have any first hand experience with mid-mufflers that work? or have any other useful options?

[R31Nismoid]

The bigger possible mufflers you can fit basically is what you need.

My 3.5" is very quiet, no drone - two massive mufflers.

They were custom, but anything big and decent works

[TiTAN]

How big is the exhaust?

My 3" is NSW rego legal and i dont have a large middle muffler its just a hotdog and a 16x11x6" rear muffler, if its 3.5" on a 33 a 16x12x8" muffler is about as large as you can physically fit on the rear 18" long at a squeeze. if you really want to just add a middle muffler i took some measurements and you can fit a 17x8x5" muffler (offset/centre for the inlet/outlets)

The people that are saying you have to get a decent mid muffler are the ones that want to have a cannon muffler sticking out of the bumper.

[SECURITY]

i THINK its a hks hi-power exhaust. looks like a 5" tip with a 4" inlet. its a 3.5" most of the way then ends with a 3" where it meets the cat. quite weird but thats what i've got. i think i'll go with a mid muffler and if that doesnt work i'll add another.

[wolverine]

The stagea has a mid muffler but Ms Wolv wanted it dead quiet so we fitted a custom 3" straight through 18" x 12" x 10" (lots of height and room back there) and it is quieter than stock.

In a bid to discourage more "random breath tests" by our increasingly pro-active constabulary I also modified the R33. It had a 3" exhaust with hotdog and largish cannon. I replaced the hotdog with a mid muffler (prob 12" x 10" x 6") and it dropped the noise significantly, later I changed to an oval rear muffler (12" x 10" x 8") and it is quieter again but not stagea quiet. Located in the Hills if you want to see want to see and hear.

[SECURITY]

The stagea has a mid muffler but Ms Wolv wanted it dead quiet so we fitted a custom 3" straight through 18" x 12" x 10" (lots of height and room back there) and it is quieter than stock.

In a bid to discourage more "random breath tests" by our increasingly pro-active constabulary I also modified the R33. It had a 3" exhaust with hotdog and largish cannon. I replaced the hotdog with a mid muffler (prob 12" x 10" x 6") and it dropped the noise significantly, later I changed to an oval rear muffler (12" x 10" x 8") and it is quieter again but not stagea quiet. Located in the Hills if you want to see want to see and hear.

have you got any further info on where and what brand the muffler is?

[BoostdR]

www.bestmufflers.com are cheap

[wolverine]

Stuart @ Racers Choice in Seven Hills sorted both cars out for me.

I have no doubt there are some off the shelf items that might suit but the rear muffler for the stagea needed custom building. This was manufactured elsewhere but I am not sure who Stuart uses.

[Dale FZ1]

I agree with Nismoid and Wolverine. To get the best/quietest result you'd need custom cans that fill the available space.

I'm running 3.5" right through, two Hurricanes as big as would fit. No drone, but it is a touch too many dB. Depending how things go over time I may have a custom can made too.

Be aware that the number of bends and pipe diameter does have a big bearing on how much noise reduction is required.

[Tangles]

Im a fan of the Magnaflow mid-muffler Resonator, ie 'hotdog'

go for a 5" body with 3.5" in/out centre to centre. ebay USA is best place to find a good price for these.

im using a 4" body with 3" in/out c/c to a kakimoto gtr racing end muffler 3" in/out centre/centre

Noise isnt that loud, a little drone at 1600-1800rpm on 5% throttle, whilst on full throttle the most noise is from the intake/turbo not the exhaust

[pistol-pete]

Sorry to dig up an old thread but I've got a related question.

Currently running a straight through exhaust on my gtr, will the car need a retune if I put my big rear muffler back on? It's quite a large muffler with a 3 inch inlet and I think a 5 inch outlet. Looking to quieten it down a little for a week or so while I daily it.

Cheers.

[boostn0199]

It will need a little tidy up in the tune.

[Harey]

+2 to Nismoid and Wolverine to fit custom straight through mufflers as large as you can fit.

I also had an 18" x 12" x 8" muffler fitted to the rear of my 34 (3.5" in and out). Its bloody massive but fitted and tucked up in there nicely. Car is super quiet but still sounds good and made good power.

[Dose Pipe Sutututu]

If any of you guys have heard of this Jap exhaust brand called St. Mays they're the most quietest exhaust I have EVER come across on any RB. I ran one on my 180SX with a RB and it was so quiet I had to chop off the rear cannon and replace it with a HKS Super Dragger for some noise, even now (my friend owns the car) when I drive the car, it would probably idle as quite as a stock Skyline and when on boost would make less noise than a V8

[Rolls]

Keep adding the largest straight through mufflers you can find until it is the volume you desire.