440lp vs 440hp

[PlumCraZRT]

Should make a note here, after late 1973, the 440 began using the cast crank, low compression came in in 1972, the blocks from 1976 and on were very thin wall and Chrysler recommended no more than .020 on the overbore. I have heard of guys boring beyond the .020 but in my opinion would be risky. The best blocks were from 68 to 72, they also had an extra rib along the upper side of each block to prevent a cracking problem, some earlier blocks had.

I would sonic check ANY block before I bored it out, regardless of year.

[brads70]

Should make a note here, after late 1973, the 440 began using the cast crank, low compression came in in 1972, the blocks from 1976 and on were very thin wall and Chrysler recommended no more than .020 on the overbore. I have heard of guys boring beyond the .020 but in my opinion would be risky. The best blocks were from 68 to 72, they also had an extra rib along the upper side of each block to prevent a cracking problem, some earlier blocks had.

For what it's worth....?
http://www.440source.com/blockinfo.htm

[Cooter]

Most will get all caught up n that "HP" thing because they are used to brand X with there "HP" engines getting all the good things like Forged crank/rods/pistons, bigger cam/better heads (Read Rectangle port), 4 bolt mains, etc.

MA Mopar just put good forged cranks in ALL the 440's up until 1972.
Brand X, 454, you might get out of say an 1973 Station wagon might be a cast crank, low comp, oval port head, 2 bolt main engine.
Then, say you got one out of a 1970 LS6 Chevelle (450 HP) then you'd get the forged crank, pistons, good rods, rectangle port heads, bigger cam and carb, higher comp., 4 bolt mains, etc.