Quote: 516 might spec at 74cc but unless it's already been milled they typically measure 84cc....
And that 8.5 C/R estimate is pretty optimistic as well...
i just milled my 906 heads 40 and there are now 74cc and those are open chambers, 516 are same chamber as 915 closed there 74-5 ccs now unmilled. you can have a 8.2 to 1 400 seen many with taller than factory deck like plus 20-25 thou. got my 906 head soo tight by also putting in 2.14/1.88 monster farera nontulup valves
I don't remember the formula off hand, but I really don't think cutting .040 is going to bring a 90cc 906 head down to 74cc.
