Cracked 2 440 blocks. They were both stoked to 505 cu. in. 3 years on each, about 400 to 450 passes each. 1st one that cracked hit water. 2nd one was cracked but didn't hit water yet. I think they were both cracked above #2 main. Both shifted at 6100, and went thru the traps at 6600 rpm.

Switched to a Bill Mitchell aluminum block 3 years ago. Between 425 and 450 passes, in 3 years. Was in great shape when freshened up this last winter. Went to 540 cu. in. when we built it with aluminum block...