I had a block that cracked around the oil pan rail and through the block. I removed the oil pan without unbolting it... it didnt take much to get the crank out eather. I had another engine that pushed the crank out through the bottom it was alot like CometGT1974's but both sides of the broke out. It took out my trans too. I was racing American Sedan and my engine spent alot of time at 8000 rpm. There were class rules that wouldn't allow 4 bolt blocks and steel cranks. We also had a problem with the crank breaking at the balancer.
I guess I am full of crap . I forgot to mention that I use a "mexican " block or a marine block that has a higher nickel content and a little lower Carbon content . At one time you could actually find them in cars if you looked for them .
The number of bolts is rather irrelevent. The amount of webbing or material, the balance of the engine, and the extra stress from power adders of stroker cranks usually is the cause of failure at high rpm. 302 blocks weren't designed for a 3.5 stroke, although they can take it to a point. There is a reason Ford beefed up the 351w on the bottom end. Looking at the photo above, does anybody think two more bolts would have helped? LOL!!!
Just having 4 bolts would not make it any stronger you are correct about that, but a Boss 302, A-4 or R-302 block (all 4 bolt blocks) would not have broken at that power level. Well maybe the Boss block would have broken but I doubt it.
