I have propane on my rig now and it works good, it's just a stock roller 302 plenty for my flatty but was lookin at efi for simplicity of fuel fill ups, also a buddy of mine just got one for his 302,I have looked at megasuirt and others as well as just possible using all stock ford stuff, I just like the flexabilty of the tuning you get with some of the other systems, just fishing for information from others.