Ok...i have a friend that wants me to ask this, he has a 1974 454 block with 4 bolt mains, etc. and he just got the urge to get the casting numbers off the heads! the numbers are 14092360, and D259. He wanted me to ask ya'll if ya'll could tell me the break down on the...valve size. ect. thanks a bunch and also where is a site that i can go to and get numbers decoded?

http://www.mortec.com/bbc.htm

Those heads aren't 74 454 heads. They're peanut-port late-model truck garbage.

The valve size probably doesn't really matter; their limits lie elsewhere.

A 74 454 would likely have 781 heads. At least, that's what my 74 Caprice 454 convertible has.

what are the limits...i have heard that peanut ports can be made into goo heads, and that they have higher airfow velocities when built right...is this correct?...and wow i guess he go ripped...lol...