[ed22]

I have a 1974 360 block purchased from a guy who says that since this block was built in 1974, which is the year after the 340's demise, this 360 was in fact a 340 core machined to 4.00" bore. This would mean that the walls of the 360 would be thicker than the standard 360 block. This would be a very good thing since I plan to build a stroker that requires boring, but is this a fact or a myth? Are there some 360's out there that where built using the discontinued 340's core?

[poncho62]

My understanding is that a 360 is a stroked 340....same bore, just longer stroke. It would be the same block

[poncho62]

If you look here

http://www.allpar.com/mopar/318.html

a 360 has a 4" bore, whereas a 340 has a 4.04 bore, so if a 340 block was used it would gain about 7 or 8 cu in.......

[ed22]

Originally Posted by poncho62

My understanding is that a 360 is a stroked 340....same bore, just longer stroke. It would be the same block

No, a 340 has a 4.04 '' bore and a 360 has a 4.00'' bore.

[ed22]

Originally Posted by poncho62

If you look here

http://www.allpar.com/mopar/318.html

a 360 has a 4" bore, whereas a 340 has a 4.04 bore, so if a 340 block was used it would gain about 7 or 8 cu in.......

That is not my question though, the assumption is that instead of having a 4.04 " bore the 340 core was given a 4.00" bore making the walls 4 hundredths thicker on this 360. So I was asking if anyone has heard of this. A am asking this with no knowledge on how a block is manufactured, meaning, do they cast a block with a smaller bore then machine it to the required bore? (in this case the a 360 could be made from a 340 core as long as originally the block was produced with a bore smaller than 4") Again, this is just something I was told, and I am just treating it a myth.