BES built a conventional headed, short deck, cast intake, single carb 611" BBC that makes 1248 n/a for a guy on here. There's a post somewhere on here about it. I'm sure someones made more with a conv. head but 1248 is stout for that specific combo.
"bad ass" Billy Gordon 632 conventional head with a true back half car that has a vin. windows and a powerglide #1 qualifier at No mercy and first round ran top et and MPH braking the drive shaft 3.9 in the run.
you can buy a motor that is a copy of his for 25K intake to oil pan bily is the engine builder call him at 540.330.9794