Rocket racer, I bought some ARP rod bolts for my '61 Super rocket,. installed them as instructed, installed the crankshaft, bolted the case half together, install the pistons and the barrel. turned the crank over by hand, and clunk the crank would only turn about 300 degrees in either direction. It turned out to be the nut of the rod bolt hitting the inside of the case. So I had to tear the motor down and put the old rod bolts in.and had no further problem. Not much room inside there.
Clive