Differential question on the 53 Commander

[lelshaddai]

I have a 53 Commander with a 63 289 4 barrel and Fight o matic with the 3.54 rear with 10" adjustable brakes. I also have access to a 3.31 Heavy duty Posi rear with 10" adjustable brakes and finned hubs. What are the advantages and disadvantages of each? How much pick up do I lose with 3.31? How much top end do I gain from 3.54? Anyone running either of these combos?

[studegary]

For nine years, I had a 1953 Commander Starliner with a 1962 259 and AT. It had the original 3.54:1 rear and 1962 V8 brakes. I drove this car a lot, including trips to South Bend (1500 miles RT). I was satisfied with the combination.

[StudeRich]

/Cut/What are the advantages and disadvantages of each? How much pick up do I lose with 3.31? How much top end do I gain from 3.54? Anyone running either of these combos?

The 3.31 has VERY acceptable acceleration and tolerable: High Speed, RPM, Noise level & Fuel Consumption.

If on the other hand you are serious about Drag Racing you want a 4.54.

You will not GAIN High Speed with a 3.54, you will LOSE IT! What you gain is how QUICKLY you get to the top end of the acceptable RPM & Speed.

I have owned and driven 3.07, 3.31, 3.54, 3.73, 4.09, 4.27 and 4.54 Studes. with Dana 44 Axles.
The best "ALL AROUND" Ratio, is the one Studebaker used the most with Direct Drive Transmissions: 3.31

[lelshaddai]

Sorry that's what I meant on the 3.54 for about losing top end.

[Hallabutt]

Anything in particular that you are looking for by swapping, other then the limited slip and of course the gear ratio? The two are both Dana 44's, and unless the one you have in there is bad, you can gain about the same gearing advantage by going to an appropriate 16" wheel and tire combination.