[Streetwize]

Yeah this thread wasn't intended to be a P!ss!ng contest.

The motor I outlined was what I felt would make the best "goldilocks/just right" type powerband for a Cobra...again my opinion only. I wanted to hear your opinions, never presumed that anyone would think I was trying to prove what was best.

The first few replies actually "got it" . It's more about tractability... and tractability is subjective, it depends on the car and how the driver likes to drive.

My 427 SBWF cruises at 65 mph on the highway and the tach is turning about 1800 (3.5 gears with a .68 od and a 28" tire) rpm, and the way I have the carb set up I can roll on to redline very easily without downshifting. But that's with a 500 horse 10:1 motor with modest sized ~200 cc ports and a 5500 rpm redline. I cruise around in fourth below 65 because to me it feels pretty much exactly how a Real 427 FE should feel in terms of torque. The motor has been running great since I first built it in 1996.

If I had a 289 FIA style car with less tire and super light like a FFR, Thats where I would build a big bore short stroke 363 and maybe a 7200 rpm redline, I would want less roll-on torque down low but produce the same HP up top....just spread out over a wider, more gradual powerband. More like an italian sports car type rev range. Yes you can use any bore stroke combo you want to make the power you want with the right heads and cam....I just like tailoring my motors to roll-on power and sound the way I want.

but there are clear 'seat of the pants' correlations between bore/stroke and how the power applies through the powerband for a given compression ratio and induction/head/exhaust flow, even if peak torque and hp are the same, I'm more concerned about part throttle drivability and how the motor pulls during roll-on acceleration. 85% of the time your motor is not at WOT....so part throttle transition of the carb circuits is real world. Cobras are a bit easier because they are light and typically have 3.50-3.90 ish rear gear ratios.

back in the early days of NASCAR running 358 small blocks, they ran bigger bore shorter stroke combos on the super-speedways, and smaller bore longer stroke motors on short tracks, mainly because they only had 4 speed transmissions and the cars were heavy.
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And Again 3000 or 3500 to initiate a dyno pull for a Dyno Mule or a Drag car is great, but 2500 is more realistic real world test to see how various motors pull on the street (from out of the basement) under real world conditions. If the engine doesn't run well or stabilize against the load at 2500-2800....Well That's exactly my point, On the street the engine does run and pull load under 2500rpm....a lot.

And I agree that with todays heads and cams, there are many more ways to make and apply power.

Sorry for any panty-wadding, It was never my intention.