The "512" that's really a 505, if you go by what they said the bore and stroke is(4.350 x 4.250).

Based on what they said the lift was going to be(mid-.600's as I recall) my guess is it's either going to get higher than stock rocker ratio, or is using a "hydrid" lobe design that's really a solid roller profile that can be run with hyd roller lifters....... Or maybe both.