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Old 06-07-2016, 08:13 PM   #44 (permalink)
Frank Lee
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Join Date: Jan 2008
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Quote:
Originally Posted by freebeard View Post
But surely the most action is taking place 90° after TDC, when the lever arm on the crank throw is at a maximum?
What a nice dream. IIRC max combustion pressure is close to TDC (right where I hate it because the leverage is so poor the explosion sits there too long with nowhere to go, pressing on the chamber, pressing heat into the cooling system ); by the time the lever is where we want it (90 deg ATDC) the chamber pressure is plummeting down and will soon be somewhat wasted as the exhaust valve opens while there's still pressure in the cylinder to get those gasses moving on their way out.

Yeah.
https://www.google.com/search?q=comb...+chart&imgrc=_
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Last edited by Frank Lee; 06-07-2016 at 08:42 PM..
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