Friend of mine with a 2TG powered Corolla KE20 and T50 trans is at the moment on a diff shop for a new gear ratio.
He uses now a 4.3 diff ratio and want to go to 3.9:1
for his calculations see: http://www.ke20.nl/Corolla/gearratio.jpg
Some further specs:
red line 7000 revs
Tire 205mm 60% 13 inch
He now drives on 165/65/13 to 165km/h on 7500 revs in 5th gear ??
Way too short
Any comments from you on this matter from transmission specialists? :P