[Christ]

Actually, that makes much more sense. If the fullness of the initial combustion event doesn't occur instantly at TDC, the burn rate increasing while the piston falls helps to evenly distribute the heat through the entire engine, rather than concentrating it at the head and uppermost area of the cylinder.

The extra liquid fuel vaporizing and cooling the chamber probably has a larger effect, but both parts seem relevant to the effect.

Guess that's something I'll have to look up sometime.

If alcohol burns slower than gasoline, does it have the same torque production effect as diesel (smoother torque application through the entire expansion cycle)?