I have heard that when you have your cvar lowered that you should also have analignment doen to match the new stance of the car to avoid premature tire wear..is this rue? If so, what suspension geometry numbers would I need if I were going to use an Eibach Pro kit on a 91 Formula with 16X8 wheels on 255 rears and 245 fronts, with stock shocks/struts for right now to avoid the premature tire wear? Thanks.

 

Yes, have the car aligned as soon as you're done lowwering the car or when you take the suspension apart for rebuilding or changing the struts.

As for the new alignmet numbers, I don't know them. However, the stock alignment specs will not suffice to take full advantage of the lowered stance.

 

My car is set up as following:
Caster:+5.5 deg
Camber:-1.5 deg
Toe In:1/16"
These have been good numbers for me, but required aftermarket caster/camber adjusters to achieve.I was surprised at how much difference the positive caster made at high speeds.
Lots of negative camber is what wears out tires real fast,mine used to be almost -4 degrees,after I first lowered the car.The inside edges of the front tires had cord hanging out before the outsides wore 50%!
They last a lot longer now.
By removing the stock plastic dust sleeves from the struts, you will gain a little more adjustability, but not as much as you can get with caster/camber adjustment plates.
If you're just lowering it for looks,try to keep the camber between 0 and -1,toe-in at 1/8-1/4".Caster's not so critical for tire wear (I think).
It will handle better than stock, even with these mild settings,since the center of gravity is lower.
Hope this helps.
-Rich-