Difference in 5-lug cars and 4-lug cars...
 

Title says it. What's the difference? Other than the obvious "one has one more lug..."

5-lug cars have four piston calipers up front for one. Bigger wheels too... 15".

Smaller brakes, smaller anti-sway bars, weaker springs/struts, non-vented rear disk...

4 lug car for sure doesn't have LSD

what exactly are the pluses of having LSD?

Not all 5 lug have the 4 piston brakes. The 89-90 GTU and 91 coupe came standard with single piston 5 lug brakes.

All of these are true if going to a GXL, 4-piston brakes w/bigger rotors I think, beefier ANTI-sway bars, LSD, and wider wheels if you get the GXL ones. And its easier to find wheels that will fit the 5-lug pattern.