I got a 52 f2 and its rather slow. Its suppost to be. Its got an f5 trany and f2 rear end. If i put a 1973 9" under the back how much more speed and.at what rpm would this put me. Also is it going to be hard to convert. I have an f1 rearend but dont know if its any good. I believe the 1973 is a 325 gear.
I'd say at a guess 3.25 gears would be too tall. Possibly something around 3.7 would be just OK. I guessing your original gears now would be around 4.11 or lower. Once you have the 9" diff installed you have a huge range of gears to choose from, which at least gives you a chance to test out stuff. Even if you borrow various pumkins and put them in to try it out. Dont forget tire and wheel size will also influence this stuff.
I think with the ****** from the F5 the 3.25 gears will be fine, that is one mightily low geared stump puller. What engine do you have in the truck? What size tires? And what is your target speed? (city or highway driving) do you know the ratios in your gearbox? If you answer those questions I can give you a detailed rpm vs gear vs speed graph.
you should check and see what ratio rear end you could find in a Dana 60 from pre 1973 F-250. then you could maintain your standard 8 lug wheel pattern all the way around. just some food for thought.
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