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Dual Exhaust Ideas... 80mm => Scraping

RBsileighty

By RBsileighty,
in Engines & Forced Induction

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RBsileighty Enthusiast

RBsileighty

Posted
Posted

Has anyone run dual exhaust on their cars at all? I am looking into running dual 60mm or 65mm exhaust due to my 80mm setup is scraping quite a bit due to my ride height.

Since the effective area is vital I can't just do two 40mm pipes to equal one 80mm pipe (2*40mm = 2513mm^2 vs 1*80mm = 5026mm^2), so two 60mm or 65mm pipes should work... just thought I'd point that out if anyone asked why so big for two... easily overlooked.

So what I was thinking is run one 80mm dump down to a Y-pipe that split into 2 60 or 65mm pipes all the way back... either exiting with two or converging back to one around the diff since it doesn't hit the ground due to the wheel.

Any experiences or ideas?

Another idea is to run oval... but it might be hard to find some pipe let alone a muffler.

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Cubes Grand Master

Cubes

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Posted (edited)

Dual is definitely quieter than the equiv single.

Bl4ck32's is amazingly quiet, still loud but not rude sounding and absolutely zero drone.

Dual = quiet. Another reason APS use it in their xr6 system.

Edited by Cubes
RBsileighty Enthusiast

RBsileighty

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Posted (edited)

Very interesting everyone... does anyone have any sound files? My RS*R 3" kit is stupid loud the way it is... sounds good but it'll take the fillings in your teeth out if you have any. Sounds like I'm definitely going dual ...

Here's how mine sounds now... RS*R 3"

Edited by RBsileighty
Ronin 09 Grand Master

Ronin 09

Posted
Posted
Its well known amongst the v8 heads a twin 2.5" is quieter than a single 3.5" with the same high quality straight through mufflers.

sorry should have qualified that one -

i agree that a twin system with the same size mufflers will be less resonant and quieter, but a 3" aussie built system with decent sized mufflers can still keep the noise down, vs a twin system with smaller mufflers (or only rear 'mufflers' in ylwgtr2's case)

:O

Cubes Grand Master

Cubes

Posted
Posted (edited)

Ronin09,

Exactly.. A 3" system. :O

3.5" systems are louder, noticably louder.

A 2 x 2.5" system is on par with a 3.5"-4" with regards to flow.

Thats what should be compared.

Bl4ck32's twin system has small mufflers on the rear, there is no droning and is only slightly louder than my 3" with a larger rear muffler and large center resonator.

I've heard a few 3.5" exhausts and to be honest they sound a little rude loud. I've now seen 2 twins on an rb30det and Tim Possinghams old RB25DET R33. Both looked to be the same exhaust, with regards to rear muffler size.

The Twin was not as rude loud.

That being said both of these twins have been on a single turbo, its quite possible twins on the gtr's twin turbo's react different.

Edited by Cubes
Cubes Grand Master

Cubes

Posted
Posted

Thats a point I missed. :O

In all seriousness though, the size of your mufflers, I expected the car to be so damn loud it wasn't funny.

Its quieter than a dude around the corner that has a 2.0"-2.5" exhaust and a cannon on his NA Corolla. :)

RBsileighty Enthusiast

RBsileighty

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  • Author
Posted (edited)
well I'm getting a full twin system shortly....

63mm thin walled stainless, straight from each of the TRUST extended dumps.

it should make a little more power and also sound fantastic..

If anyone has sound files of duals... I'd love to hear them... however, ground clearance is point #1 for me since my Kei Office puts things really close to the ground. Not much could be louder than my 3" RS*R with no resonator and no cat so anything on dB limiting will be an improvement.

Edited by RBsileighty
Oosh Veteran

Oosh

Posted
Posted
Yes its quieter now with its straight-through system, than with the old single 3" exhaust with the cat.

Oosh- ill try to get pics, but i aint got a camera :P

That'd be good but don't sweat it. :D

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