400

Hum, not sure about that...A lot of trucks and motor homes had a front sump. I was meaning are there some numbers on the pad or anywhere that specifically means...this was a truck engine.
There is... I posted the stamped pad in the OP. I don’t know how to figure it out after the first couple. i.e. the sequence number is where I get lost. I know that the damper is significantly thinner than the cast crank damper from my 12.3.76 date 440