1989 GT, recently purchased, not much of a gear head, but am diving in head first and want to try and learn as much as I can.

When I turn left and smash it, the car will go sideways, but when I am making a right and smash it, only the right wheel spins. I was also told that the car has 3.73's

My first of many questions for you guys is:

If this was a posi car this should not do this right?

Second: If the car does have 3.73's what rpm should I expect to see at 70mph in 5th gear?

I am also looking to go to a 4.10 gear. how hard is it to install a posi, (if not installed) and the gears? That is all the questions for one night many more to come. Hoping not to be a pain in the A$*.

Thanks,
Neil

1989 Mustang gt

List of current mods to car:

BBK longtube headers,
BBK Off-road X-pipe,
Flomaster Cat-back,
BBK Cold air intake,
BBK 70mm Throttle body/EGR spacer,
MSD 6A Ignition box,
AutoMeter monster Tach,
Pro5.0 short throw,
Flex-Lite electric fan,
UPR Underdrive pullies,
2 inch drop springs,
UPR Sub-frame connectors(Welded)
17 inch Cobra wheels
Centerforce Clutch
T-5 trans