Stock cast rods are incredibly strong and stable parts....right up to the point where they BREAK! This happens without warning and usually takes the whole engine with it. Ya, ya, I know, scores of folks running 10's with well prepared cast rods, here it all the time. Some things to ponder on:
About 15 years ago we encountered another racer at a local track. He had a beautiful early GTO, Nash 5 speed, RAIV heads and used an old solid cam. The car ran well into the 10's and he spun the engine well past 6000rpm's. At the time I was amazed, so we got on the discussion of engine durabilty.
He said that they shot peened, magged, polished, resized and installed new bolts in factory cast rods.....they snapped like twigs on the very FIRST run!
The next effort involved rebuilding an early set of SD forged rods with correct heat treating, etc, etc, bent them into "S's" on the FIRST run!
Ordered custom Crower billet rods and they ran season after season without any issues. At the time the only real trouble he was having was keeping a rope seal in the 400 engine.
For what it's worth, back in the 70's when I was in high school lots of us had "Muscle Cars", mostly Mopar's and Chevy's. The few who ran Pontiac's were constantly scouring the salvage yards for spare engines. We catagorized the Pontiac engines for having "soft" internals, so we avoided them at all costs.
30 years later, I have no doubt that the cast rods were the death sentence of so many of these engines. Of course non of us back then even looked at the tach when doing "donuts" in the high school parking lot at FULL throttle or during grudge races on the street. One very close friend of mine went through about a half dozen Pontiac 400 engines in less than two years....he was a barbarian behind the wheel and his foot was constantly pushing a hole in the floor board!
For what it's worth and my opinion, complete waste of time to bead blast, shot peen, polish, resize, good bolts, balance, etc a set of cast rods these days when you can buy good forged rods at reasonable prices that are many times than the cast rods would ever be after all the time/expense. If nothing else you will sleep better at night and have much less of a "pucker" factor when you spin your big Injun to past 6000 rpm's if a good set of forged rods are in place!......Cliff
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