From what you've seen when OEM 440 forged cranks develop cracks, do they tend to show up in the same general area, e.g. are they more likely to occur in the main journals than the rod journals?

Also, do the upgrades (band-aids?) that can been done w/ an OEM block, for example using a girdle, cross-bolted main caps or aluminum caps, seem to have any influence on where the crank cracks develop?

Thanks!

From what I've seen they all crack in the mains at the rolled fillet. The rolled fillet design is great for OEM engines but not so hot for 500+ hp, especially sustained duty. I think the factory engineers recognized that problem back in the day and went with a different design for the NASCAR stuff. Those old NASCAR motors from the 70's made about as much power as a lot of street guys these days!

The only crank I ever broke was a Crankshaft Specialist forged crank that broke on the number 5&6 rod throw. Totally broke off of the crank and into the side of the block.

I usually see them cracked at the undercut fillet. As for what precautions? Just the usual stuff. Avoid detonation, Good balance job, quality damper, proper main saddle bore alignment.

MB

The #4 main is where I've seen a lot of them crack. CHIP