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r_towle |
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,598 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
so, I have been thinking (not always a good thing)
If an engine is basically an air pump, and the objective is to make it as close to 100 percent efficient, why is the exhaust valve so much smaller than the intake valve? Forget emmisions, forget fuel delivery, just want to understand why this is so...it is so on most engines... Rich |
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michel richard |
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,291 Joined: 22-July 03 From: Longueuil, Québec Member No.: 936 ![]() |
Cause on the exaust stroke there's a hard piston pushing gases out, while on the intake stroke there's only soft atmospheric pressure pushing the mixture in. I suppose the exaust valve is made smaller because larger is not needed, and would there fore be a waste. Plus there's a ton of other concerns such as gas speed etc . . . that I don't fully understand.
FWIW, my .02 Michel Richard |
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