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By-pass Valve On The Exhaust.

cobrAA

By cobrAA,
in Engines & Forced Induction

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cobrAA Mentor

cobrAA

Posted
Posted

Hello,

I ask on this forum because there's so much people on here I'm sure some peoples can feed me some infos about this kind of setup.

I want to install an open-valve on my exhaust line to gain more power on the high-way and track. I really want a quiet ride when cruising in the street but would like something more agressive on the highway or for drag night.

So, my mechanician told me that one of his customer gain 60whp with that kind of valve. I guess he install a Y pipe before the catalyser but I can't be sure..

Feedback!??

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R31Nismoid Grand Master

R31Nismoid

Posted
Posted

Load of shit. Your mechanic needs the sack :)

If you have a decent, well contructed and flowing exhaust - then dropping it (or bypass) should see little to no difference in power at all.

You can have a quiet exhaust, and free flow, and make 350rwkw easily. It just costs money as you need decent mufflers.

PM-R33 Grand Master

PM-R33

Posted
Posted

....oh ok. Sounds like a lot of f**king around for no point really.

My mate had something similar but a lot more practical. A normal exhaust with a screamer plumbed in and a section before the cat that unbolted and turned the screamer into atmospheric. Took 10 mins to swap the little Y section. Was done purely for being able to have the sound for track work/fun on the street but probably made a little bit of a performance increase due to not having to run all the gases through the exhaust.

If anything maybe the OP should do something like this.

cobrAA Mentor

cobrAA

Posted
  • Author
Posted
Was done purely for being able to have the sound for track work/fun on the street but probably made a little bit of a performance increase due to not having to run all the gases through the exhaust.

This is exactly the result I'm looking for because I will be sad to never heard back the sound of my RS*R GT2 ( but it's tooo loud for street).

By the way, it would be an electric valve, just like this one ( excepting the Apexi is mechanic):

http://www.nengun.com/apexi/exhaust-control-valve

PM-R33 Grand Master

PM-R33

Posted
Posted (edited)

Hmm like i said seem's like a lot of mucking around and a bit of money involved in fabricating it all and buying the electronic valve. Personally i would just do what my mate did, not as convenient cause you can't swap it from one system to the other while driving, but only takes a few minutes to swap the section of pipe in the garage.

I have a universal varex muffler underneath my car with the electronic valve control to make it quite if need be, but i'm going to get a straight 3" pipe to replace it if i want to. The muffler is quite bulky and heavy as hell and im sure it would still have a restriction on it even when fully open.

Edited by PM-R33
Don Dada Mentor

Don Dada

Posted
Posted
Hello,

I ask on this forum because there's so much people on here I'm sure some peoples can feed me some infos about this kind of setup.

I want to install an open-valve on my exhaust line to gain more power on the high-way and track. I really want a quiet ride when cruising in the street but would like something more agressive on the highway or for drag night.

So, my mechanician told me that one of his customer gain 60whp with that kind of valve. I guess he install a Y pipe before the catalyser but I can't be sure..

Feedback!??

WTF is a mechanician???

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