H-Beam rods?

H beam is the way to go. Use full groove main bearings( you have to by two sets of 1/2 groove) to have a full time supply of oil to the rod bearings. All the cylinder pressure is gonna put a load on those rod bearings.

I noticed in another thread that you have what looks like a small block with a B&M on top. (maybe i'm dreaming again) What are you using for pistons?

Jack