360 Head Casting Numbers?

[blackace]

I got a set of 360 heads on a 318 I have sittin my garage. What are the casting numbers and how do I know if they are "X" or "J" heads?

 

[Lars]

I have a set of "J" heads and there is a large "J" cast into them on the outside. I assume it would be the same for the "X" heads. Not sure though.

 

[340mopar]

Here is a list;
http://www.moparts.com/Tech/Archive/smallblock/6.html

The 2513894 is an "X"
The 3418915 & 3671587 can be "J"

The reason I say "can be" is I have seen some 3418915 as "O" and "U"

Also the 3418915 is the head Mopar used for the T/A head, the intake pushrod hole on this head are offset away from the intake port.

 

[fishy68]

Look down between the spark plugs on the outside and that's where you'll see the letter cast on the head if it has one and most do but I have seen a few that don't. It's about an inch in size so if it's there you'll see it. The casting number can be found under the valve cover or underneath the intake runner of the head.

 

[blackace]

The casting number on the head is 348915-A but I don't see anything else on them that has a letter to indicate whether it's a J head.

 

[fishy68]

The last 3 numbers are the tell tale sign. There 915's. J heads. Like I said earlier a few didn't have the letter cast onto them. Also if you notice you posted the casting number is 348915 not 3418915. That's something else ma Mopar did strange but there the same head. They just left the first "1" out of the casting # on some heads.