I had an OT truck with factory optioned 350, TH375 (TH400 with TH350 tailshaft) and 2.41 gears with 29" tires. It was actually really nice to drive. Not a rocket by any means but highway cruising was perfect and mileage wasn't too bad.
I ran a 3300 LB 50 chevy delivery with a saginaw, vega 4 speed [3.40 ratio 1st gear] and an Olds gutl*** 2.29 rear axle [!]...The secret is all in the gearing for 1st gear. I have no idea what a C-4 uses but the slippage from the ******'s converter should help. With a light car such as your model A, even 31 inch tires [that's what mine were] you should be just fine and get great mileage on the hiway IF...if you go conservative with the cam selection. Go with a short duration cam and you'll be fine. I used a 292 degree cam in mine but I had 406 cubic inches to tame it down a bit and the 3.40 first gear was low...worked absolutely great around town and went about 196 MPH I suppose.
Where do these guys come from? Lower gear ratio numbers, ie 2.75:1 obviously result in higher speed at same RPM. Higher gear ratio numbers, ie 4.11:1 obviously result in lower speed at same RPM. Over drive ratios, considered less than 1:1, ie 1:0.76 obviously result in higher speed at same RPM. High or low rear end nomenclature refers to resulting speed at same RPM, not the low or high number compared to 1:1 straight drive. Example: Compare with transmission gear ratios with first gear obviously lower but higher number. Simply put high gears refer to high speed, low gears refer to low speed. I hope this helps clarify non-believers.
Sorry Bean, I didn't need a dictionary to know what gear ratio means, any engineer knows that, unlike some HAMBers. But you are right about picking battles. When you try to educate someone, they often drag you down to their level ...
Sometimes it is best to try and figure out what they mean and let them be dumb. Some just know not and know not that they know not.
Not sure how well they accelerated , but the Ford Granadas ran 2.79 gears ( 8-inch rear ) with a 302 and C4. You might be ok.
The C4 probably has about a 2.46/1.46/1.00 ge****t. There might be other combinations available out there, but this is the one seen most often. My roadster ran a mostly stock 302/C4/3.00 gear/30 inch tire combination for a long time. It was fine everywhere, but really shone on the highway. I think your 2.75 gears will be fine as long as you understand the nature of the compromise they entail.
I've got 2.73 gears behind my 401 Nailhead and SP400 in my 3500 Lb. '50 sedan delivery. With the monster torque and switch pitch converter I have no problem smokin em any time. Out on the highway its a real cruiser too. best of both worlds. as far as the high gear low gear debate, I relate a high gear to High Speed not a high numerical ratio. Same with a low gear, its a low speed gear not a low numerical ratio. Everybody I know uses the same terminology.
Because there are; 1. People that jump in spouting bad information. 2. People that post repeatedly to do nothing but boost their post count. ~Alden
Now you know why it's important to study math in school. Get your GED and understand 4:11 is a low ratio.
What seems to be overlooked throughout this discussion relating to the OP's original question is.............the sbf/C4/2.75 or 2.79 is what a large percentage of Fords came with from the factory........and they worked just fine.......the difference here is that the tires are a bit taller, but that would seem to be offset by the lighter weight, and therefore lower inertia, and the car should perform well enough for the OP's stated purpose. Oh, btw the way....on the higher/lower terminology debate.......what is a common 'nickname for 1st gear in a transmission ?......why, I believe that is called "low" gear..... Ray
this just popped into my head while reading this. my 61 Dodge has to high a rear gear. it's like high gear on a 10 speed . harder to pedal. soo my 2:90 ?? are higher than my previous 3:73's that just popped into my head mid thought so it must be the right way and everyone else is wrong.