We actually built the test engine for KRE's 500hp "crate" motor. This was before they made the KRE heads.
We used unported 87cc Edelbrock heads, Crower 60919 cam, Rhoad's lifters and high ratio rocker arms.
That engine made 505hp/551tq, idled with 12" vacuum at 750rpm's, and pushed a 3900lb 1971 Firebird to mid 11's at 118 mph on it's first outing, and was driven to the track.
I think the results pretty much speak for themselves.....Cliff