I agree about the sweet-spot rpm. I run at 60-65 mph for better gas mileage (261 with 2-barrel Holley AA-1 carb used on 302/270 GMC engines).
4-speed/3-speed - why does it matter? Both are 1:1 in high gear.
Yes, I have have tubes. My Cooper dealer put them in. I'll not use tubes on the '54 I am restoring - it had primo original wheels. I have been driving with the radial/tubes for 9+ years.
I was wondering about 3 versus 4 speed myself, but not regarding high gear. I was wondering about how first gear with a 3 speed performs on steep slopes. I have some steep boat ramps and carry way too much equipment in my boat, and am worried about pulling up the ramp with 3.55 gears and 31.5 inch tires. I currently have 3.73 rearend (1970ish)and stock rims with radial tires (outside diameter unknown), and I don't have a lot of power out of the hole on steep grades. I have a 52 235 Blue Flame, BTW. Would I be better off with a 4 speed or a T-5 if I went to 3.55 gears?
