The stock gsl-se has 135 hp compared to 142hp for the 86-88 2end gen cars ( 160 hp for 89 up). It has has a smaller throttle body and smaller intake runners. The 13b in the gsl-se has two piece apex seals instead of the three on the 86 up+. Those engines last forever. I have 3 with over 200k that still run.

If you compare the two cars weight wise, the gsl-se was a fully optioned car only. No base model, power everything. A base model 2end gen is only around 100 lbs more. Howeve, when you remove all the non racing items from the gsl-se the weight difference between the two really climbs.