so basically the point of the swap is to upgrade from a 4.08:1 final drive to a 4.77:1:?

Could one just swap the ring and pinion gears instead of the whole enchelada?

 

That must suck on a streetcar.....youd be doing nothing but shifting all the time!
Even my rock crawling Samurai doesnt have gears that short.
Personally,if you want better acceleration,Id recommend a light flywheel.Youll get the quick revs,but none of the RPM limitations of the ring and pinion (mechanical wear,fuel consumption,low topspeed).

 

gsl-se has 4.10 ...gsl has something like 3.91... but yes you can change just the gears from the kia to the rx7 diff

 

ah, I see. I'll consider that for my EV project