440 block casting number identification number help

Yep, the dash number is the number of core plugs changed in the casting core....highest number I've heard of is 13. Some think the higher the number, the higher the likliehood of core shift...never been proven.

Welcome to the world of Mopar castings. There are several things to note:
1. Any block can be a good one or a bad one. Casting quality is all over the board.
2. It is safe to say, keep the overbore minimal. More power can be lost to flexible cylinder walls than found by a few more cubic inches.
3. The only way to be sure of a particular block is to sonic check it.
4. The " '75 and newer blocks are thinwall" statement promulgated by official Mopar insiders is BUNK. Later blocks may be made of slightly softer material, but cylinder wall thickness isn't statistically different.
5. Mopar blocks are known to have decks that are not perpendicular to each other and/or not parallel to the crankshaft centerline.
6. It's been noted that many 400 blocks have seven good holes and one bad hole. Sleeving the bad hole is an acceptable option. Properly done, the sleeve is as good or better than the other holes.
7. Look at the pan rail to see if any marks there may indicate an oversize lifter bore. This has been known to happen although it's rather rare.
8. The "dash number or "casting core revision number" is no indication of how good a block is. Sonic testing has revealed that there are unusable blocks with a -1 number and super blocks with a -12 number.
9. I REPEAT, THE ONLY WAY TO TELL IF A BLOCK IS GOOD IS A SONIC TEST.

R.

There will be a casting date on the side of the block as well as a VIN stamp on the oil pan rail. There is also ID info on the ID pad.