340 Head Markings

[Mr.FT]

Looking at a 340 for a buddy of mine , block has the 340 markings but I don't see an X or J on the heads. Should this throw up a red flag??

Thanks

 

[1970Duster]

No. Heads do get changed, as long as the block has the 340 cast on the side your all good

 

[684mulas]

Under the valve cover should be a casting number that you can hopefully find on this list. Most any year 340 or 360 head will work well on a stock 340 or 360 engine. 894 and 915 (casting #) heads are the most correct but 1975 and newer will have hardened valve seats which is not a bad thing either.

http://www.mymopar.com/headcastnumb.htm

LA Engine Cylinder Heads Casting Numbers

Casting Number Engine CID Year Intake Exhaust
2465315 273 1964-65 1.78 1.50
2532080 273 1964-65 1.78 1.50
2536178 273 1966 1.78 1.50
2658234 273 1966 1.78 1.50
2658920 273/318 1966-67 1.78 1.50
2843675 273/318 1968-74 1.78 1.50
2268341 318 1962-67 1.84 1.56
2658234 318 1967 1.78 1.50
2843675 318 1968-74 1.78 1.50
3769973 318 1975-83 1.78 1.50
4027163 318 1977-86 1.78 1.50
4027593 318 1977-84 1.78 1.50
4323302 318 Fast Burn 1985-86 1.78 1.50
4323345 318 Police 1983-86 1.78 1.50
2531894 340 1968-70 2.02 1.60
3418915 340TA 1970 2.02 1.60
3418915 340 1971-72 1.88 1.60
3671587 340 1973 1.88 1.60
3418915 360 1970-72 1.88 1.60
3671587 360 1973-74 1.88 1.60
3769974 360 1975-76 1.88 1.60
3671587 360 1976 1.88 1.60
4027569 360 1977-86 1.88 1.60

 

[fishy68]

If it's a 73 340 it'll have 587's and they don't usually have a letter designation.