I'm in the process of building a 2 bolt main 400 sbc with a +.030 bore. It's got a fresh grind on the crank (still has the grind sizes in marker on it) and I'm sending the block to get checked in the next few weeks. The engine was running when I got it, with a stock intake and cam, but smoked, I found a burnt piston skirt but no damage to the cylinder wall. I do not know how to measure the rods for length. I've heard there are 5.7" and 6.0" rods for the 400's. I took a quick measurement from eyeballed center of the wrist pin to eyeballed center of the crank bearing and found about 5.7. Worst case, if I'm too dumb to figure it out, I'll just get new rods and pistons when I buy my rebuild kit and cam. Are 6.0's better than 5.7's?