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Stock Exhaust - Is The Gtr Better Than The Gtst

benl1981

By benl1981,
in Engines & Forced Induction

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benl1981 Grand Master

benl1981

Posted
Posted

Hi there,

I have heard people making high awkw on the GTRs with stock exhausts.

I'm aiming for 240rwkw with my rb25 - currently 3" turbo to cat --> 3" catco cat -->3.5" catback (kakimoto)

Its not real loud but would like to quieten it further. Would a GTR catback fit? How much power would this rob?

The kakimoto already has 2 mufflers.

Anyone have first hand experience?

thanks

skybarge Community Regular

skybarge

Posted
Posted (edited)

Keep the current one

What most people do for stock exhaust 2.25" GTS-t round 2.75" for a GTR

is replace it form the catback, GTR/GTS-t catbacks are the same, it's only the front pipe which is different.

Your 3.5" exhaust is definitely large enough for the power goals you are chasing, even a 3" would do for that power :)

Edited by skybarge
dano4127 Veteran

dano4127

Posted
Posted

is the kakimoto the JASMA one? thats the one i have and it purs just nicely if you want quieter than that you need a cup of harden the f*k up! :) most people think mine sounds stock till you over 5k

Beer Baron Grand Master

Beer Baron

Posted
Posted

I have a 33 GTR with a stock exhaust. It's pretty awful. it's very tiny, heavy and restrictive. It's one of the things nissan used in order to keep the power under the 206kw agreement. They were quite smart though. They used reasonable dumps, pretty good front pipes (on GTR) and a good cat, then put a strangling exhaust on it, becuase of this a modifier can reap a much bigger than normal gain when changing cat back exhaust on a GTR. thanks nissan :)

The Mafia Grand Master

The Mafia

Posted
Posted
Thanks Beerbaron - sounds like its not a good idea then.

Daniel - Yeah I have the Jasma one. It is pretty good but around 2000rpm cruising it is a little dronny..not much though. Its actually quieter at 4000rpm.

mine is the same, I'm currently looking for ways to quieten it right down.

Trust33 Grand Master

Trust33

Posted
Posted

pay the exhaust man $1k plus and you will have a quite + free flowing exhaust.its all in the type of mufflers you use.

or you could stick with your current setup and just throw a silencer in the exhaust tip.or yopu could buy an apexi exhaust valve (which sits in place of a flange gasket i think).which can be remotely activated from within the cabin via a lever and cable setup.

  • 1 month later...
Beer Baron Grand Master

Beer Baron

Posted
Posted

consider using thicker wall mild steel pipe. in my experience it definately cuts down some of the resonance and 'drone' and helps mute the note a little too. thin walled stainless pipe is always loud and resonates a lot.

benl1981 Grand Master

benl1981

Posted
  • Author
Posted

Thanks Beerbaron. Might make up a 3" in MSteel modelling my kakimoto.

Does anyone know exactly what the GTR Cat back size is?

Is it 2.75 or 2.5" ?? Is it in fact bigger than the GTST?

I was thinking of keeping 3" Dump/front --> 3" Cat ---> GTR Standard 2.75? Cat to rear muffler (chop and weld on flange) ---> Kakimoto rear muffler.

Cheap way to see if quietens it down while still making ok power.

Anyone got a GTR cat back (minus muffler for $20? hahah)

Beer Baron Grand Master

Beer Baron

Posted
Posted

trust me the stock GTR catback may be better than the GTST one, but it's no great shakes. I'm not sure if it's 2.5 or 2.75 but I'd say 2.5 if I had to guess. plus it has lots of bends as it follows the body fairly closely. It is fairly easy to make an exhaust that flows as good as the stock one, yet makes more power. as I said the standard GTR exhaust is made partly to keep power out put down, not up!

benl1981 Grand Master

benl1981

Posted
  • Author
Posted

So what is a good muffler/ resonator (and cheap) to weld into that pipe from cat to rear muffler?

I have heard the oval off centre entry ones are good..I guess the bigger the better for noise abaitment

Might grab some 3" pipe

3" should flow 240rwkw right?

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