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r_towle |
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 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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Al Meredith |
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Senior Member ![]() ![]() ![]() Group: Members Posts: 973 Joined: 4-November 04 From: Atlanta, ga Member No.: 3,061 ![]() |
I have read some on engine basics (no reguard to number of cylinders , configuration ETC) and the intake to exhaust ratio is +/- 75%. Try this on just about any stock engine and I think you will find its close. I also read that the theoreticle (spelling) limit for a 4 cylinder inline is 2.2 Liters. The pistons get to big and get "buzzy" at high rpm. Once again, think about it , how many four cylinder engines are bigger than 2.2 L ? Some are but they use balancing shafts.
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