[dana44]

Valve sink, where the valves, usually the exhaust, will beat the valve into the seat because they were too soft and couldn't take the extra heat once lead was removed from gasoline. Ford and Chevy were more prone to this than the Mopars. I have never had a problem with my Mopars having valve/seat problems, whereas I saw many a problem with Fords and Chevys. Just goes to show the quality of the materials Mopars had in them.

ImperialCrown showed the boss that shows the block stamping right above the driver side of the timing cover and in front of the intake manifold at the corner of the head. The other casting numbers, including the date of casting (anywhere from 3 to 12 or more months before installed in a vehicle), are on the driver's side of the block. It won't tell you car or truck, but it does verify casting, engine size, and six digit date, along with a day or night clock for casting time.

Car or truck would be mostly the camshaft profile, something that is not identified on the block, sorry. But, there may be something with the intake manifold and most likely the exhaust manifolds, as trucks used different ones, at least in the later 60s.

 

[dana44]

At this point, let's go with identifying the block from the cast numbers for the date cast and the size of the engine itself. These numbers don't lie because they are raised castings, not stampings, and can't be faked based on its design.

 

[dana44]

Did you ever get the engine up on a lift to look at the cast numbers and date on the engine?