Originally Posted by R/T1968R/T
516 heads are approx. 84cc in factory form. 915 heads are approx. 79 ccs in factory form. you can still build a good quench motor with them.

Me thinks those are Mopar furnished specs, not actual as produce sizes, I believe the 516 has smaller chambers than the one year only 915 heads had shruggy

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)