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So shorter stroke motors want more advance.? I always thought it was combustion chamber design ?
See that 444 on Meyers facebook that made 547 ft/lbs was using OE 2v heads, so I assume open chamber and still only wanted 31 degrees and has the long 4.35 stroke. Also low rpm motor but piston speed is high
 

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Discussion Starter #62
That makes sense, with less stroke you'd have slower piston speed and need more advance?
My line of thinking here is ,, that the flame speed is more or less a constant, at IIRC around 60 FPS, therefore the bigger bore and or the faster the piston speed is {and maybe other factors} the more advance you need to get the flame front to the other side at the correct time for best cylinder pressure. I am happy to hear otherwise as this is somewhat theoretical
 

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My line of thinking here is ,, that the flame speed is more or less a constant, at IIRC around 60 FPS, therefore the bigger bore and or the faster the piston speed is {and maybe other factors} the more advance you need to get the flame front to the other side at the correct time for best cylinder pressure. I am happy to hear otherwise as this is somewhat theoretical
I agree with bore other than if tight quench and small chamber then does bore matter as much? As far as piston speed it slows back down and hangs at TDC longer but gets to TDC faster, thats why I felt long stroke, long rod combos could get away with less timing and are less prone to detonation on the same octane fuel.
 
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