Great info here. Thanks!
Use of the engine is general hooligan driving. Motor aside, the car is built to be as well-rounded as possible with suspension/brake upgrades, weight reduction and chassis mods. I'm really interested in a responsive motor that makes mid-400s and pulls to (or close to) 6k. So...more roadcourse than drag strip. I plan to never commute or be stuck in traffic in this car.
I was planning on leaving the bottom end alone though I realize that 6k is asking a lot of this rotating assembly and I would have to upgrade this sooner rather than later.
Good call on the lifters. I'd have to add that in...
Trickflow specifies the Harland-Sharp rockers. Part description says "must use." It sounded like there was something specific about those particular rockers but f there's a lower cost alternative, that would be helpful.
Yes, I was comparing the head swap on the current motor to the Blue Print long block because I'd likely be able to transfer my intake/carb/water pump/balancer etc. over to the new motor.
It looks like they do use Edelbrock heads so you're absolutely right that it's not an apples:apples comparison in that regard. IMO, because they dyno test the motor I wouldn't worry so much about some janky head castings causing flow problems. It's good to hear that the Edelbrock heads may not be as rough as I have heard though!
As for your big block build, how are you making that kind of power for so cheap? I know the OEM heads are pretty damn good on those engines...and IIRC the performance versions have forged cranks, right? But there certainly is no replacement for displacement. :)