[DUG]

You do not have to raise the compression to get power out of LP, you just have to time the engine so that it makes use of the slower burn rate of LP. Upping the compression of the motor is just going ot make more power by creating a higher cylinder pressure before combustion, this applies to gas, LP, diesel, LNG etc... While propanes higher octane rating will help keep the detonation down it will stop detonation no more then gas of a simalar octane rating. Plus you get even further increased CHT over a normally hotter burning LP motor.

I had my distributor recurved and run a lot of initial advance on my 350 and get damn near the same power I did on gas out of it. I think my only real loss of power is coming more from a lack of fuel then anything else, I don't think the 425 carb and model J converter I selected supply enough air or fuel.