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  #1  
Old 10th March 2012, 06:39 PM
robo robo is offline
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Default Clever exhaust

http://www.impulsengine.com/how/header.shtml

Some cleverness about exhausts, worth a read.

Bob
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Old 11th March 2012, 07:30 AM
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Frankly I think that is mostly over egged rubbish! "Must be used with synchronised valve timing" What? They haven't even matched the lengths of the primary tubes! Lots of pseudo techy words on that site but mostly meaningless in my humble opinion.

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Old 11th March 2012, 09:05 AM
robo robo is offline
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There must be something in it because F1 have been doing the stepped ring exhaust thing for a few years now.

Bob
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Old 11th March 2012, 09:21 AM
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Have a close look at an F1 exhaust system and you will find that all the primaries are the same length. Yes a properly designed and "tuned" exhaust system can help deliver slightly more power just like the inlet tract length can affect power delivery but it has to be matched to the speed at which you want the power to arrive. This exhaust manifold is poor by comparison, by not having equal length primary tubes the different cylinders would get different amounts of reduced pressure to pull the fresh charge in. That's never going to be good for overall power production.

F1 intakes/engines/exhausts are designed as a whole to get the max out of every piece. They are designed to produce their power at extremely high revs and all components are designed to work together to achieve absolutely maximum horsepower.

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Old 11th March 2012, 09:29 AM
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Having had a proper look at that website I can only come to the conclusion that its either a joke or aimed at gullible people with more money than sense or knowledge.

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Old 11th March 2012, 12:20 PM
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I wont comment on the primary length issue or the any of the other technical blurb. What they are saying is that a smaller primary coupled to the stepped collector tube will increase the exiting exhaust speed. That in turn with some trickery on the valve timing will net an increase in power by partly pulling the intake charge before slamming the exhaust valve shut which causes a ramming effect. I think....... Bottom line is the stepped exhaust system is on all the top race cars now nascar,F1 and bikes etc.

Edit this is a head spin on the subject http://www.performanceforums.com/for...-67265439.html

Bob
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Last edited by robo : 11th March 2012 at 03:55 PM.
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