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Location:
Kita-Ku, Sapporo, Japan
Registered:
January 2003
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Re: no muffler?
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Mon, 04 October 2004 15:19
 
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| thu187 wrote on Tue, 05 October 2004 01:07 |
as you may have guessed i don't know much 
why is exhaust restriction good for low revs?
isn't it better if the air is allowed to keep flowing through?
i have no idea, i hope somebody can answer that
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if cam timing is such that there is a lot of valve overlap, then at low rpm the fresh intake charge will tend to flow out thru the exhaust valve while both are open.
if you have a restrictive exhaust, the backpressure will stop the air/fuel mixture going out the exhaust before the exhaust valve closes.
at higher revs, this pressure builds up and makes it harder for exhaust to get out, reducing 'power'.
basically, if your engine needs backpressure, then you have selected a cam with too much valve overlap..
but thats just my unfounded opinion 
read a book called "the scientific design of intake and exhaust" or similar. by P.Smith.
Cya, Stewart
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| | Subject | Poster | Date |
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no muffler?
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thu187 | Sun, 03 October 2004 13:02 |
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Re: no muffler?
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mrshin | Sun, 03 October 2004 13:07 |
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Re: no muffler?
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thu187 | Sun, 03 October 2004 13:10 |
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Re: no muffler?
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dimmy77_03 | Sun, 03 October 2004 13:20 |
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Re: no muffler?
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mrshin | Sun, 03 October 2004 13:21 |
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Re: no muffler?
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thu187 | Sun, 03 October 2004 14:28 |
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Re: no muffler?
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thu187 | Sun, 03 October 2004 14:30 |
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Re: no muffler?
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greenta22 | Mon, 04 October 2004 13:19 |
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Re: no muffler?
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STR8 2.8 | Mon, 04 October 2004 13:21 |
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Re: no muffler?
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oldcorollas | Mon, 04 October 2004 14:09 |
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Re: no muffler?
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thu187 | Mon, 04 October 2004 15:28 |
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Re: no muffler?
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thu187 | Mon, 04 October 2004 14:54 |
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Re: no muffler?
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oldcorollas | Mon, 04 October 2004 15:00 |
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Re: no muffler?
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thu187 | Mon, 04 October 2004 15:07 |
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Re: no muffler?
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oldcorollas | Mon, 04 October 2004 15:19 |
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Re: no muffler?
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thu187 | Mon, 04 October 2004 15:22 |
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Re: no muffler?
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b1gb3n | Mon, 04 October 2004 16:33 |
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Re: no muffler?
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jesseT18 | Tue, 05 October 2004 00:55 |
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Re: no muffler?
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Norbie | Tue, 05 October 2004 02:31 |
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Re: no muffler?
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b1gb3n | Tue, 05 October 2004 02:41 |
