318 combo
Propane motors love compression and timing. I see it a ton in the off road world because it allows the motor to run a funny angles. Its considered the poor mans fuel injection. 13:1 compression is nothing unusual if propane is your fuel of choice.
Its easy to run a turbo on propane too. Just plumb it in as a blow through carb, connect a line to the intake manifold for a boost pressure to the back of the mixer and ta-da, you are now boost referencing the fuel pressure.
The only issue of running propane is you have to have good vacuums to get it to start up. High compression and the big cams, don't lend them selves to that.