Found This Interesting Page On The Hamtramck Registry

Rob R said
Iron heads ported by Ron's in the US..titanium valves,retainers and locks.some of the very first sheet alum intakes.C M/P index 9.00 to 9.99 most could run under the index.
Click to expand...

but what "iron heads" and what did they flow?

they would have to flow well over 350cfm to take a motor over 8k.