[Yetiman]

What Jaguar did your rear end come out of ? Typically they have a 3.54 in them (Thats what was in mine from a 62' XKE, and in my 75' XJS and 83 XJ6)'

In my Cobra it has been changed out for a 3.07 as the car had traction issues with the 3.54 and turned too much rpm on the freeway.

I am running 295/50/15 tires and a Doug Nash five speed. The trans has a 3.27 first gear and a 1:1 fifth gear (5 speed, no overdrive).

That combo works pretty well. It's able to hook up pretty good in first, and turns about 22-2500 rpm at 60ish MPH.

You must also consider your engine configuration. Is it a built motor that turns big rpm and breathes well (while lacking some low end power) or maybe it has a strong torque curve but looses it's breath at 5k rpm.

It will play a role in your gear choices as well.

My engine has OK low rpm power, strong mid rpm power and pulls hard to 6700 rpm. I can lug it around a little around town, but when it's time to make things happen I need to get the tach flying.