RPM heads-(Edelbrock)

Ohh k Looking for a bit of information on RPM heads. My build is a 66 383 .30 over flat top pistons (10:1 CR).Lunati cam 268/276@50 duration,Valve lift 494/513. The RPM heads im looking at are available in 75cc,84cc and 88cc My question is which ones do I order?Thanks for any help, this is all new to me :(