Can someone help me identify the heads on my 440. The cast numbers appears to be 2406516. The 6's and 8's are hard to tell the difference but I'm asuming it either a 516 or 518 scince I see no heads with a 2408pre-fix. My problem is these heads have a 1.74 exaust valve and measure 83cc chamber. From what I can find the 516 would have been a 73cc chamber and the 518 would have had 1.88 exaust valves. The chambers do not appear to have been altered. I could under stand enlarging a 516 valve to a 1.74 but the chamber still should be 73cc. I'm sure there not max wedge 518 because the exaust valve would have been 1.88 and the intake runners appear to be of a normal head. Anyone ever here of this comb? help Mike

it's probably a 516 , max wedge would have huge intake ports .

where are you getting this 73cc number from ?

blueprint for a 516 casting is 78cc. It is widely recognized, however, that most all heads were deeper than blueprint, and 83cc sounds about right. Conventional wisdom is that Ma did this on purpose figuring racers would work with their motors to bring them to blueprint, which would be higher compression than Mom's grocery-getter.

1.74 exhaust valves have most likely been installed at some point prior to you taking ownership, as I don't think any 516 castings came with them and it has been a fairly common thing to do since most BB heads have the 1.74 valves. With the 1.74's installed, they're pretty effective heads. Great for a 383 build, where you may not need the larger port flow #'s that a 906 casting offers, but do need the closed chamber to gather compression.

It's likely a set of 516's with the bigger ex valve added.

I've done some closed heads with nail head type valves, and a small amount cut off of the deck, and then they come down to the 78 cc spec.

A set with stock style valves, and some wear on them will be more.

i heard/read once that some very early production 67 440 R/T & GTX engines had 516's w/ the 1.74" exhaust valve.
no way to verify that though.

i seen 67 915 with 1.60 and 1.74 so no way 516 have 1.74

I fully understand that the valves could be changed, but most casting number charts show the 516 should be around 73cc. Mine cc'ed out at 83cc. Is there a chart that you know that shows the 516 to be at 83cc.\?