I have used 2 MP cast cranks w/4"stroke. The forged were not available yet when I got these. I built 2 408"/360 for dirt track applications..Ross pistons, Eagle rods, solid flat tappet cams, W2 heads/intake. Made 500+ HP and 500+ ft/torque on dyno. They both were run in 3200# cars. Both were run 2 seasons before problems. The first one showed signs of cracking after mag-flux and was replaced with a forged MP crank. The second one showed NO signs of cracking, so was returned to service,,#5/6 crankpin pulled out the 3rd race of season. The MP forged crank had to be turned under on the mains before I could use it. It was .001" to big and .001" out of round. I don't use alot of MP anymore.