383 head casting number question

[Doc Corey]

Got this 383 with my Challenger. F383 stamp at dist. I pulled the valve covers to read the head casting and found number 34823gap 6 on both heads. They are hard to read. I am posting pix in hope someone will know the answer.

 

[Doc Corey]

That last 3 might be an 8

 

[MOPARMITCH]

F383 should be a 70 engine. not sure on the heads...

 

[cuda6bbl]

3462346 is a 1971-73 head.2843906 is 1968-70 head.

 

[340challconvert]

F383 is a 1970 engine

With a 6 as the last digit; Your heads are most likely:
3462346 – 1971-1972, 383/400/440 B/RB-series big-block, 2.08/1.74 valves, 79.5cc
or
3462346 – 1973, 400/440 B/RB-series big-block, 2.08/1.74 valves. 81.5cc

The only other head casting ending in 6 is the 2843906 - 383/440 1968-70 2.08 1.74, as cuda6bbl noted

 

[340challconvert]

Here is a good article in Hot Rod on Mopar bb heads;
Cylinder Heads Part I - Tech Articles - Mopar Muscle Magazine - Hot Rod

 

[Chryco Psycho]

Both are open chamber heads , as it starts with 346 it has to be the 346 heads , the 906 has a slightly better intake port

 

[Doc Corey]

Thanks for all the info guys, but why the gap in the numbers? And on both heads. Was that just missing from the casting tag in the core box?

 

[Chryco Psycho]

who can say, apparently the casting molds were defective & not repaired

 

[DetMatt1]

F383 is a 1970 engine

With a 6 as the last digit; Your heads are most likely:
3462346 – 1971-1972, 383/400/440 B/RB-series big-block, 2.08/1.74 valves, 79.5cc
or
3462346 – 1973, 400/440 B/RB-series big-block, 2.08/1.74 valves. 81.5cc

The only other head casting ending in 6 is the 2843906 - 383/440 1968-70 2.08 1.74, as cuda6bbl noted

View attachment 68285

516’s, just sayin’

 

[340challconvert]

Good point; it is possible that he has older style heads on his 70 block?

2406516- 361/383/413/426 1964-67 2.08 1.60

516’s, just sayin’

 

[340challconvert]

2406516-6 early model closed chambered heads.
They came on many 383's up to and through 67.
The hi-po 67 440 also had closed chambered heads...the 915 but with larger ports and exhaust valves.
The 516 heads usually came with the smaller 1.60 exhaust valve

 

[Chryco Psycho]

I have used many sets of 516 heads , they are my second favorite head to use being closed chamber & add a hardened seat port the heads & use 1.81 exhaust valves , they friggin work great !

 

[Doc Corey]

It's not a matter of me using them. I just want to properly identify them and the engine for interested buyers. Thanks for all the info

 

[DetMatt1]

2406516-6 early model closed chambered heads.
They came on many 383's up to and through 67.
The hi-po 67 440 also had closed chambered heads...the 915 but with larger ports and exhaust valves.
The 516 heads usually came with the smaller 1.60 exhaust valve

View attachment 68296

Both the 516s and the 915s have small 1.60 exhaust valves and the 915s stamped with HP had 1.74(iirc) exhaust valves. The 516s were used on all the ‘66 440s as well and the early 350 horse 440s in ‘67 such as the one in my silver Imperial. The 915s took over for the 516s on the 440 for the ‘67 model year.