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Twin Exaust 5K

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Hi guys have a fully worked 5k wich has a 2 1/2 inch exaust system

considering about putting twin exaust on it but not sure how it wil sound or go!

Just wondering if anyone has done it before?

As far as I'm aware the engine would not produce enough exhaust to create back pressure, unless 1'1/2 or smaller pipes were used. what diamiter twins are you thinking of?

 

EDIT: worded wrong

Edited by Chillin

Hi guys have a fully worked 5k wich has a 2 1/2 inch exaust system

considering about putting twin exaust on it but not sure how it wil sound or go!

Just wondering if anyone has done it before?

Why ?

Generally on a four banger its a pointless waste of money and extra weight that has to be carried.

It'll have more of a burble from the exhaust, if you have the pipes as a "4 into 2". Somewhere along the system have a "H" pipe or a cross-over pipe so that you might be able to regain some of the lost power.

As far as I'm aware the engine would not produce enough exhaust to create back pressure, unless 1'1/2 or smaller pipes were used. what diamiter twins are you thinking of?

I think the word your after is "scavenging" not so much back-pressure. Besides, someones going to bring up that back-pressure isn't needed and then someone else will come back with "yes it is".

If i remember my maths correctly, and i can't be stuffed hunting it up, the cross-section diameter of two 1 1/2" pipes would be just a little smaller than the single 2 1/2" pipe.

 

 

Really the only time a twin system would be ideal is when the cost of fitting the twins takes up less room then that of a 4" 5" truck exhaust. But even then the area inside the circle doesn't change very much (if at all) when its flattened into a rectangle.

 

 

Unless your just thinking of twin pipes after the muffler. Then thats a bit different and go for it, but don't waste your money on having a pipe either side of the car.

Twin 1&3/4" would be equal in cross-sectional area to 2&1/2" pipe- 1.5" pipe is only 2/3 the size.

 

If you had 4-2-1 headers and took separate pipes from each pair of cylinders it would sound different. Run 1 & 3 into one pipe and 2 & 4 into the other.

 

In the end, probably not worth the expense...

Have seen it done to an old datsun stanza. Made a nice burble almost like a V motor. Did have a bit of poke but guttless compared to after they went back to a single pipe.

 

If you went to the trouble of setting the exhaust up like a v4 motor, having the extractor pipes length tuned and figuring out where to place the cross-over pipe along with its size. It should go alright. But alot of trouble, time and money to replace a single pipe, something that can be bought "off the shelf" so to say.

  • 2 weeks later...

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