383 Cast Crank?

[IQ52]

IF it is a 1971 383 cast crankshaft, the damper number is 3577180. The cast crank 383 & 400 use the same torque converter balance. You cannot use a cast crank 440 converter because the 440 uses the same amount of weight but a different distance on the torque converter from the crankshaft centerline than the 383 and 400.

However..................B&M claims you can use this flexplate on all '71 and up 383, 400 & 440 externally balanced engines...........

http://www.jegs.com/i/B-M/130/10237/10002/-1

 

[Harryhemi]

The engine is a 70 2bbl. The engine was overhauled quite sometime ago and believe the crank was cut .10 under, but don't remember about the forged or cast crank. I'm going to take it over to my buddy's garage and put it up on the lift and pull the oil pan and I could possibly pull the damper and see what casting it is? If the B & M flexplate works, then could be the answer?

 

[IQ52]

It being a 1970 2-bbl is is most probably an internally balanced engine. Best to make certain though.