hp vs 6pak stampings

[70challengerrt]

I am looking for a 440 time correct motor. If I had 2 blocks; one a 6pak and one a hp block side by side how can I tell the difference with out removing the heads (asssuming the heads are the same cast number) or oil pan? Or are all 70 blocks cast and stamped on the pad the same?

[Green Drop Top]

While individual block have variable stampings such as the assembly date and letters that indicate special machining to that particular block such as undersized lifter bores, crank journals, etc.

Any HP 440 block would be stamped the same as any 440+6 block, there are no differences between the two except the parts inside them, and even those are'nt that much different. same heads, same block, same crank, same rods, etc. The VIN sequence number stamped on the blocks oil pan rail raised machine pad could indicate if the car the engien originally went into was a 6 pack or 4 barrel car, but that's the ONLY sure way to know what the block was originally assembled as.

[70challengerrt]

Thanks that is what I needed to know. It seems like everybody has the 440+6 blocks but no one has the 440hp which I need. So I will look into the 6pak blocks.

[Chryco Psycho]

if it has the 6 pack bootom end the balancer will be offset weighted

[moper]

Everybody has the 6bbl blocks for one reason. People assume they are better, and "rare", so they get more from them. There is no way to tell other than having an exisitng VIN match. SO, any HP of the right vintage "could" be a 6bbl, and vice versa.