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Old 19th February 2010, 03:11 PM
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Default Exhaust???

Hi,

while we are all waiting for a certain somebodies test results, just thought I'd throw a question out there.

Does the exhaust have to be made from round tube???

I was thinking (probably shouldn't), to keep the side of the roadster clean looking and with a close proximity to the ground - could you not make the exhaust (main system) from rectangular tube?

Obviously the silencer would be an issue, but rear engine cars seem to manage. Repositioning of the fuel tank might have to done to get the silencer where the fuel tank would normally be.

Twin exhausts out the back - whats your thoughts??
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Old 19th February 2010, 03:26 PM
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I have often thought about having the exhaust exiting out the rear but there just isn’t enough room.

But now you mention rectangular tube under the car.

My initial thought, without thinking to hard about it (trying to play the wii) have a 30mm by 300mm box section.

But like you say a silencer could be problematic.

I might need to sleep on it. I have my best ideas when I am a sleep.

Cheers Ginge
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Old 19th February 2010, 03:31 PM
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Quote:
Originally Posted by gingea1pom View Post

I might need to sleep on it. I have my best ideas when I am a sleep.

Cheers Ginge
Sorry Ginge, but we don't want to know about your thoughts when you're asleep......
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Old 19th February 2010, 03:56 PM
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No reason why you couldn't ..... but firstly I expect the flow characterstics would not be that good. It could also be quite difficult to manufacture, bends etc. If your looking to save space, then the critical parameter will be the cross sectional area. As the flowrate of the gas will be the same up both exhausts, the cross sectional area will dictate the gas velocity which is the key performance parameter. If you take a 35mm diameter pipe has a CSA of 962mm2, then you need a 31mmx31mm square to match that CSA.
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Old 19th February 2010, 04:04 PM
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I do like the idea of twin pipes at the rear but with the car only 5 inches from the bottom chassis rail to the tarmac i,m not sure how it could be done,

sleeping policemen would be a pain to get over i imagine.

cheers
andy
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Old 19th February 2010, 04:08 PM
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Excellent,

Working on that theory if my exhaust is 1mm x 962mm, I maintain the correct CSA, Hardly any decreas in ground clearance.

Does anyone know where I can get some 1mm x 962mm box section and a silencer to mach.

Cheers Ginge
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Old 19th February 2010, 04:26 PM
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I had the same thought of twin rectangular section.. As I have a V6..

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Old 19th February 2010, 05:27 PM
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Quote:
Originally Posted by gingea1pom View Post
Working on that theory if my exhaust is 1mm x 962mm, I maintain the correct CSA, Hardly any decreas in ground clearance.
I'm guessing the 17.5x increase in exhaust system surface area will have some effect on gas flow.
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Old 19th February 2010, 05:35 PM
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On a plus side would the increase in surface are not reduce temperature?
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Old 19th February 2010, 05:58 PM
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How big a silencer is needed on a normal 2.0 4 pot car?

I will need 2 smaller ones, one on either side.

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