That's a great chart, but looking at I I may want to think about going 255.1...guess I have to think it over some more Posted using the Full Custom H.A.M.B. App!
I not sure why anyone would want to run 2:55 gears! Salt Flats maybe, but not on the street. We are talking Hot Rods here right? Did you mean 3:55? Even that is way to high for my blood.
I RUN 250 gears in my zephyr,and have since I built it in the late 90's trans is a 4L80. my 58 delray I swapped between 250 & 275 dependending on trans ,700r or sagnaw mid 80's with OD. I'm paying attention to this thread because I'm about to build a 50 chevy with a 261 It's to be a KUSTOM not a racer. I haven't played with a SIX in 50 years. And where I live in CA the left lane if you are not doing 85 you will get hit in the Rear. Sam Foose was the last one to get hit. OH iI forgot my 48 cad also has 275's those are all all big block chevy's
This man speaks the truth! learn to do the math! A simple formula is [RPM X Tyre Diameter] ÷ [Ratio X 336] = MPH To reverse this formula to get ratio is [RPM X Tyre Diameter] ÷ [MPH X 336] = Ratio Example 2200 RPM with 25-1/2” diameter tyres at 65 MPH. 1: 2200 RPM X 25.5 = 56100 2: 56100 ÷ 65 = 863.07 3: 863.07 ÷ 336 = 2.568:1 overall rario 4: 2.568 ÷ 0.7 = 3.66 [Rear end ratio] Note you shouldn’t have the cruising RPM below the torque curve. AND below the stall of the converter [unless it is a lock-up type that still functions ] If you’re not good at math, a $5.00 pocket calculator will do it for you.
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