I'm running a mild 493" RB with 10.2 to 1 (Cranks 200 psi & runs on 91 octane), Indy EZ non-max wedge port heads that flow 345" at .600 on the intake, a well-massaged aluminum 6pack intake, a Porter spec'd mild solid roller with non-needle bearing axle lifters and the old DC mechanical 2bbl carbs. The pistons and pins are below 540grms and it has 7.1 inch steel rods.

It pulls hard to 6700 rpm, gets nearly 14mpg all day long on the freeway at 70mph with 4.10's and the Passon and it pulls away from Hellcats whether from a stop or on the freeway. Everything fits under the shaker hood although it's a tight fit. I guess my point is, you don't need to get too fancy to accomplish your goals. Keep it simple. It's the combination.