First off, HUGE THANKS to TheMAN for the idea to swap in the Altezza Torsen LSD!!!!'

I just finished the rear transplant, still have the front to go (today's project). Took for a test drive in 2wd for obvious reasons. So the result: The way I drive, really no significant functional loss of torque in the hills. The acid test is getting out our driveway. There is a steep part and it is dirt/gravel, so both torque and traction are needed. My first impression is I think it actually does better on the driveway test because of the torsen. I can get a little more running start in higher 1st gear revs, then no loss of traction up the steep bit with the LSD kicking in to help.

TheMan, I think you have an auto trans, correct? I'd expect a palpable feeling of loss of torque with that tranny. But the manual has a very different first gear ratio.

So the full story about the gearing and torque results:

I had an auto tranny in her, and she totally lacked torque in 1st. Bogged down hard getting up the driveway. But, the manual trans has a very different set of gear ratios.

Auto 1st gear ratio 2.452
Manual 1st gear ratio 3.704

That is a factor of 1.51, with the manual tranny I gained that much in low end ratio in 1st gear for climbing hills! Super!

The difference between the 4.3 diff and 3.72 diff is 1.16. 51 minus 16 is still 35% higher in first gear than the starting point with the auto tranny.

On the other end, high gear,

Auto tranny ratio 0.73
manual 5th gear 0.854

That is a loss on high end ratio for highway cruising of 17%, but swapping in the 3.72 brings it back up 16%, almost to the auto trannys overdrive So final end ratio to the wheels is only 1% different than the auto tranny overdrive.

So, end result, best of both worlds, way better torque in low range than the auto trans, and just about the same ratio in high gear cruising the highway.

Now I just need to add a gear box for speedo recalibration.