dyno numbers, help explain

[philbay]

This data was on a Dyno jet rear wheel dyno.. Car is 1970 chevelle, 454 30 over, 4 speed,355 posi,781 oval heads, 27" tall tire. 3 pulls. 332.55hp and 414.16 tq.,,,,,,311.55 hp and 415.72 tq.,,,,,334.53 hp and 428.64 tq....... On the data sheet I noticed at no time did the rpms reach 4000 rpms.. Can someone explain why that is.. The builder who did the heads said that I had a mild cam . Before I had the heads done, because the seals and guides were shot and passing blue smoke. Yes he checked for a leak down with the pistons... I felt the car pulled just fine to just over 5000 rpms. Can anyone tell me whats happening and are these numbers right? what kind of et can I expect,,ballpark.. thank you phil