Originally Posted by sscanrun
it could be a 350, 327,305
vin # ko126tbm
Your title lists the casting number as 3970010, if this is indeed an 010 casting it is the highly desireable heavy duty 4 inch bore block that was used for some 302's and 327's and a ton of 350's. It was used as a basis for high performance passenger car engines as well as heavy duty trucks and industrial engines. It is found as 2 or 4 bolt mains, the only way to know is to pull the pan. 2 bolts are good and 4 bolts gooder. If a two bolt this block easily converts to 4 if that much strength is needed. It is of course a 2 piece rear seal and has no factory provisions for a roller cam.
The factory id stamping ending in TBM leads you to this being from a large van with a 350. The fact that the id stamp is legable probably means no one's tried to rebuild the thing a good thing for the hotrodder as many rebuild jobs only serve to screw an otherwise decent block up. figure coming out of a van, what you've got a darn good bottom end to build on that will need a decent set of pistons, heads, cam, intake, etc. to build a strong running hot rod motor.