440 heads
 

Checked the head #'s on a 1966 440 motor I picked up. The last 3 numbers are 516 Just wanted to know if these are good heads. They should be the original.

Are they part#2406516 ?

head casting number
 

Yes

the 516 heads were closed chamber heads like the 915's but did not flow as well as the 915's of 1967. with some work you can make them work fairly well in a street application. A friend of mine had a set of them on his 70 GTX that worked very well. (11.70's back in the 80's). He used them cause he could not find a set of the 915's and he wanted the 516's for the compression gain. He used a big cam. They were ported and bigger valves were installed.

The heads in question were produced from 1964-1967 and they were put on the following engines: 361,383,413,426. These are what was referred to as 300L heads. They came with a 2.08 intake and a 1.88 exhaust valve. They had a chamber of 73.5cc.

Are you sure the exhaust valves are that big? I'm thinking the 516's exhaust was more like 1.60 and the intakes were 2.08 like the 915's. Correct me if I'm wrong.

Well I have two references that have two different numbers, 1 is 1.60 and 1 is 1.88