'79 440 Motorhome short block - Should I buy it?

probably cast crank, see if the seller can get the casting number off the side of the block or a digital of the vibration dampener on the crank to be sure. Also what's the number and letter before the 440 stamped into the flat portion on the top right hand corner of the block. I'm pretty sure that the 440 last year of build was 1978.

Terry