So I'm looking into building up a 400 sbc two bolt main I have. I was wanting to go with an internally balanced crank, 6 inch h-beam rods and pistons with around 10 - 10.25 compression. I'm also thinking about going splayed 4 bolts on the bottom end. I'm still debating on whether or not to try and go higher duration and lift vs. low end torque/power. It will be going in front of a T-56 so I don't think I'll be seeing that much in the way of high RPM's but I still keep thinking about high lift/duration cams, ha ha. I'm currently running 3.42's in the rear and would be moving to a 4.10 or 4.56 gearing since I'll have a .50 final OD gear in the transmission.

My main concern is how hard would it be to go with a 6 inch rod with an internally balanced crank. I've read that you just can't buy any internal crank due to clearance issues with a 6 inch rod. Is it just the crank I need to worry about with that length of rod or will I need to clear cylinder walls, oil rails and run a small base circle cam also? I've read that with a 6 inch rod it helps with TDC timing as the piston hovers there a bit longer and allows flame front build up which is god for naturally aspirated motors. Plus it is supposed to relieve stress on the cylinder walls.

What are your thoughts on this?