interesting
everyone else said it, I didnt want to be left out!
my only question to your theory is: assuming that there was a lot of gas vapor in the crankcase, very possible by the way, what would cause it to ignite? it would need a spark or a huge amount of pressure (the latter is very doubtful). if there was a lot of gas vapor in the crankcase, the oil would have smelled like gas, did it? and also, if you were dumping that much gas into the motor, the cylinder walls would have been washed out and you would have pretty nasty scratches on the walls from the oil being washed away by the gas.
if there was an explosion in the crankcase, there should be some other evidence, such as discoloration of the metal.
just some things to think about
