Disappointed magnum head flow numbers....

Flow benches and dynos are tools you use to compare change and they will differ from each other even if the same make and model then add an operator can skew or alter numbers based on setup, which isn't bad, you just need to test the same way every time. So ideally you want to measure a set of heads then port and measure again to see gains.

Are you buying ported heads or buying something bare and doing some home porting?