I think the BSP engines are a great platform to start with, they come with the max stroke crank, cc's are usually very close to where they should be, and the piston is up in the hole consistently, and as far as i can tell, the heads that come on them are a good casting also. I have one of these BSP engines, and it makes great power in stock form. Add a billet flywheel, more timing, more air and fuel, bigger pipe and some better valve springs along with the right cam and you have a torqy motor.