Race cars in
Join Date: Oct 2007
Location: South Africa
Only the final drive differs (the gear ratios are the same) - so all gears are affected.
The 2.5 box is 37km/h per 1000 rpm (red-line 259km/h)
The GTA box is 39km/h per 1000rpm (red-line 273km/h)
The 3.0 box is 41km/h per 1000rpm (red-line 287km/h)
AFAIK you'll need to change the crown gear (on the diff) and the secondary shaft.
In all honesty the 3.0 box is too long - At highway speeds the 2.5 box sits at 3200rpm, where the 3.0 box sits at 2900rpm - below optimal torque. You'll have to shift gears for inclines more often
Last edited by Gertie; 05-01-15 at 07:58.