What all do you need to do the conversion besides the inj. lines,head,cam & timing cover? Im starting with a 12V it has a rotary pump on it

 

Wow, pretty much the only thing you're gonna be able to reuse will be the block, crank and rods. For doing that, I would seriously reccomend picking up a 24v engine to start off with. Even one with a cracked block or bad crank would be a good start. Be cheaper to get a 24v than to buy the parts new or used. Then it would be onto the 12v parts like the timing cover, pump, lines, gear, linkages, etc.

 

I already have the pump, & injecter lines. Pistons arent that expencive but the rest of the other stuff is