gearbox standard ratios are not good with a 3.7 C/W weak diff and fragile teeth not much use for big power or top speed, so i enlisted a transmission company called G.E.A.R.S tv to build me a box....................Specification is as follows

3.05 crown wheel & pinion
quaife ATB diff ,modified 12-bolt crown wheel to fit diff
shimmed diff to obtain correct preload
late high ratio gear set (3.15 1st gear) similar to rs turbo ratios
new bearings,syncro rings nub shifing plates and tension springs
cryogenic treated gear set