Does the HO have a steel crank and the non HO has a cast? I believe that the cam is what creates the firing order right? Please correct me if i'm wrong because that seem to be happening alot latley. Because i have a custom grind that is for a HO engine with the firing order 1 3 7 2 6 5 4 8. I was just mainly wondering if the block, crank and rods were the same. All imput helps, thanks for the help so far.

perfect so if i buy a non HO roller engine from a 89 lincoln town car if i change the pistons the short block will be the same as an HO?

Perfect i thank you very much.