2.66 low gear vs close ratio

vntned
That tranny is perfect for 3.91s and your 170.All except those pesky splits.Unless you supercharge it!
This gearset really wants a car-weight to engine-size ratio of not much more than 11/1, and an engine with plenty of torque that can pull from idle to 2500 or a bit more.It's pretty much essential that the engine be able to pull hard from just off idle; say 1200rpm.
At 170 cubes, you are on the short side all right.I'll assume your vehicle is an early A with a weight of 2600pounds. Then 2600/170 = 15.3/1. That's pretty out there. If you are heavier it get's worse. You probably won't be much lighter. Not so it counts anyways. If you did turbo-charge it, you might/could get into the zone.Lotsa cash tho. Good used 225/318 would be way cheaper.