The Ford Barn - View Single Post - What gears in a stock '48 F1 with 9" rearend?

tubman · 03-25-2024, 11:43 AM

It kind of makes a difference by where you are; mountainous or hilly country vs. the flat plains will make a difference. So will tire size. Also, are you going to use it as a truck a substantial part of the time?

I have 3.55's in my '51 coupe (no overdrive) with 225/75R15 rear tires and it's just fine. 2300 rpm at 55 and 2700 at 70. 2700 rpm's seems to be to be the maximum comfortable speed my engine wants to run for a sustained period of time. In addition, my engine is a little more than stock; a '51 Mercury with prepped Edmunds heads, a 2G carburetor, and a Mallory dual point.

I think the 3.50's may be the best choice. You can fine tune it after using it by going up or down a couple of sizes on the rear tires if you have to.

03-25-2024, 11:43 AM	#4
tubman Senior Member Join Date: Dec 2013 Location: Minnesota, Florida Keys Posts: 10,396	Re: What gears in a stock '48 F1 with 9" rearend? It kind of makes a difference by where you are; mountainous or hilly country vs. the flat plains will make a difference. So will tire size. Also, are you going to use it as a truck a substantial part of the time? I have 3.55's in my '51 coupe (no overdrive) with 225/75R15 rear tires and it's just fine. 2300 rpm at 55 and 2700 at 70. 2700 rpm's seems to be to be the maximum comfortable speed my engine wants to run for a sustained period of time. In addition, my engine is a little more than stock; a '51 Mercury with prepped Edmunds heads, a 2G carburetor, and a Mallory dual point. I think the 3.50's may be the best choice. You can fine tune it after using it by going up or down a couple of sizes on the rear tires if you have to.