First year 440 cylinder heads?

[66Satellite47]

I am curious which intake port design and combustion chamber design the 250 head has and the valve size.
The 516's had the smaller 1.60 exhaust valve compared to the 915HP & 906 heads with 1.74 exhaust.

 

[Jerry Hall]

I am curious which intake port design and combustion chamber design the 250 head has and the valve size.
The 516's had the smaller 1.60 exhaust valve compared to the 915HP & 906 heads with 1.74 exhaust.

The non HP 915 heads also had 1.60 exhaust valves.

 

[1968rt]

I have seen a few 68 383 2 bbl 290HP motors that had 516 heads from the factory! Maybe early builds

 

[OKDart]

I am curious which intake port design and combustion chamber design the 250 head has and the valve size.
The 516's had the smaller 1.60 exhaust valve compared to the 915HP & 906 heads with 1.74 exhaust.

According to Mymopar.com, 250 heads have same size valves as 906. 2.08/1.74 and is open chamber. I'm not sure about the port design, I didn't compare them when I had them off the engine.

It is interesting that the 2843906 have an earlier P/N than the 2951250, but the 250 came out before the 906, and then wasn't used after the 906 was introduced.