I know this will seem like blashphemy to performance V8'ers, but since the six and the gen2/gen3 8's all weigh more or less the same, what about running a 360 massively detuned?
Move the torque peak as low as possible, period. 300cfm 2-bbl carb (or equiv FI), you could get away with single exhaust, etc.
Here's a little chart. I had one with my T150-OD trans. I plugged in a 2.22 axle. OD is obviously silly with this motor/axle. Tire size is 205-70/R15.
Should be easy to tune a 360 for this! Pointy cam, no overlap. Smoooooth and quiet too!
But maybe the V8 with it's 33% more internal friction is a big ose for this, over a six. (8 pistons/valve jobbies vs. 6.) The low RPMs would help offset that though.
Run 50psi in the tires, 10-weight in the trans and axle... kidding.
TEST HACK ENGINE 1st 2nd 3rd OD RPM CFM MPH MPH MPH MPH 1000 89 15.8 19.9 35.2 50.3 Axle ratio n:1 2.22 1100 97 17.4 21.9 38.8 55.4 Tire diameter 26.3 1200 106 19.0 23.9 42.3 60.4 3.78=9/37 1300 115 20.5 25.9 45.8 65.5 3.31=13/43 1400 124 22.1 27.9 49.3 70.5 3.54=11/39 1500 133 23.7 29.9 52.9 75.5 1600 142 25.3 31.9 56.4 80.6 RPM interval 100 1700 151 26.9 33.8 59.9 85.6 T-150/OD 1800 159 28.4 35.8 63.4 90.6 First 2.23 1900 168 30.0 37.8 67.0 95.7 Second 1.77 2000 177 31.6 39.8 70.5 100.7 Top 1 2100 186 33.2 41.8 74.0 105.7 OD 0.7 2200 195 34.8 43.8 77.5 110.8 2300 204 36.3 45.8 81.1 115.8 2400 213 37.9 47.8 84.6 120.8 Engine CID 360 2500 221 39.5 49.8 88.1 125.9 VE 0.85 2600 230 41.1 51.8 91.6 130.9 2700 239 42.7 53.8 95.2 135.9 2800 248 44.3 55.8 98.7 141.0 2900 257 45.8 57.7 102.2 146.0