Exhausts

ECUs, intakes, turbos, fluids, transmissions, exhausts etc.
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fatboyzlim
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Post by fatboyzlim » 05 Dec 2005, 12:39 am

Hi Guys,

Wondering if I could get some feedback on going the dual split exhaust option.

From a performance standpoint, I am wondering wether having dual exhausts would actually result in a loss of power.

If you think about it, you are effectively doubling the volume of the exhaust after the split. Does this result in a loss of back pressure?? If there is a drop in back pressure, can this be rectified through using a different type of exhaust, i.e. not a straight through design??

Anyone got any ideas or experience with this?

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Alpha
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Post by Alpha » 05 Dec 2005, 2:50 am

Loss of power will depend on the diameter of the downpipe of your exhaust which should exactly be the same as the one coming out straight from the turbine.

Simplify: A diameter larger than that would make the engine throw out *more* of the gases than it actually should and that will result in power loss. Similarly, too small diameters will increase the pressure load on the engine and it will not be able to dispose off those gases at the required speed. Thus, an increase in boost due to overload of pressure but = engine breakdown in the long run.

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fatboyzlim
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Post by fatboyzlim » 06 Dec 2005, 10:43 pm

what difference would it make coming into 2 cats and two pipes rather than a split after the cat?

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Alpha
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Post by Alpha » 07 Dec 2005, 12:06 am

fatboyzlim wrote:what difference would it make coming into 2 cats and two pipes rather than a split after the cat?
Well, I think the catalysts are just for the sound of each exhaust pipe :roll: The overall effect of the two should just be a bit more than of just one big catalyst on one exhaust pipe (just a guess)..

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Post by mikeh » 20 Jan 2006, 7:42 pm

*sorry to ressurrect this thread* :)

What car are we talking about?

Basically, while a dual exhaust on some cars look better.. it might, as Shash said have a reverse effect on the performance.

Are we talking about a turbo'd engine or not?

To me, a 4 banger, 2 liter engine doesn't need dual exhausts.. If you start talking about bigger engines (more cylinders and/or capacity) then i'd say why not.

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Accord98
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Post by Accord98 » 20 Jan 2006, 9:54 pm

i think were talking about FatBoys
Mitsubishi Magna 3.5L -- superdupper larger than life charger ..... heheeh j/k :P :P :wink: :wink:

But yea 3.5 Magna .... would look awsome wit a dual exhaust!

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fatboyzlim
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Post by fatboyzlim » 21 Jan 2006, 12:13 am

fatboyzlim wrote:but sounds like farting underwater
You will lose back pressure, which means that you might sacrifice low-end torque for higher power. Though, fbz, I think your car has a fair share of low-end torque (hence your 3.5L)..

I'm thinking about going to a custome pipe (probably 2.25 or 2.5 inch) with supersprint mufflers at the end. Supersprints are progressive mufflers, and don't have this typical aftermarket illegal sounds... but if you put your boot down, it sounds aggressive

..and that my style. Will help you with registration and such as well..

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fatboyzlim
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Post by fatboyzlim » 21 Jan 2006, 12:15 am

Accord98 wrote:i think were talking about FatBoys
Mitsubishi Magna 3.5L -- superdupper larger than life charger ..... heheeh j/k :P :P :wink: :wink:

But yea 3.5 Magna .... would look awsome wit a dual exhaust!



would look awesome even without it :P :P

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Wicked
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Post by Wicked » 21 Jan 2006, 4:23 pm

if its a turbo get one from the turbo 2.5 inch and the end make it three and put it as one exhaust and not dual ones :( but u better stay to regulations about the noise but power will be there u wont lose much ... since yr name is FAT better stay with one FAT exhsuat bro will be mean ... and sounds loud and good unless u need to fit a silencer coz here i dont know if they allow the noise ask somone who knows regulations about it



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