First of all a stock stroke on a 428 is 3.98" and in a 427 it is 3.78". All things being equal a 427 should rev a little higher than a 428. The biggest problem with original 427 was the factory rod bolts, ARP has fixed that. The lifter problem is the next to overcome. I once twisted a 406 up to 8400 RPM. That turned out to be an oiling problem. A sideoiler should not have the same problem. I was and am currently using shell solid lifters ,tubular pushrods. I'm using the Dove rocker system. The weight of the valves were once a big chalenge. I remember the use of hollow sodium filled valves to get the weight down and get dissapate heat. I remember a movie "REDLINE 7,000" I don't realy race my car and have the adjustable rev limitter set to 6,000 rpm. It gets to that rev limit in no time at all, usually surprising me. If I leave the rev limiter set at 6,000 rpm and the
oil is warmed up I should be OK.