'I've got to tackle a 10 year wait in rebuilding the engine in my '72 very soon. It's a 454 that was downrated in '72 to 270hp (? as I recall)
- what modifications did you make to get 540hp? I assume you're running premium gas - any problems with pinging?'
ME: Owen, Remember that the 270 h.p on your vette is 'RWHP', so gross h.p. on that is roughly 310 . The mods i did to get me from 390 gross hp to 540 were : New Edelbrock Oval Port Heads which have huge ports and valves compared to stock, New Edelbrock AirGap Dual Plane Intake which has huge runners versus stock, Demon 850 cfm, dp, mech. sec. Carb , new Hydr. Lunati aggressive Roller cam/roller lifters/roller rockers , Hooker Super Comp. Headers , 100 % fresh air thru L88 hood and plenum, twin electric radiator fans which dont come on if im moving at least 35 mph and its less than 80 f. outside, and running motor at 180 f. instead of running at stock of 190 f. My buildup was mostly patterned after author Hib Halversons successive articles called : BIg Block from Hell series.
'At this point I'm looking at a basic factory-stock rebuild but am considering bumping the compression a tad. I believe stock was 8.25:1 for '72 - considering increasing to 9.5 or so. Anyone think that would be worth it in seat of the pants feel?'
ME: No..i dont believe it will afford you that seat of the pants feel Owen ; I think youre going to have to shoot higher if you want that thrown back in the seat feeling when you mash it. The best single think you could do , is to pop for new Oval Port Heads.
'The setup is 3.08 rear, auto-trans, fully optioned (meaning heavy and lots of power accessories.)'
ME: If you want good low end torque, you need to do a rear gear changeout. Mine was a stock 3:36 --- a 370 made a big difference. However, if you do alot of highway driving with your vette, keep your
3.08.