[spannerman]

I'm just interested, how modified is the car? Several thousand dollars for a close ratio gearbox that may only make a few tenths of a second difference at best. A more cost effective way to chase time may be with diff ratio and especially an LSD or locked diff, or even with better/stickier tyres. If we work together we can beat those pesky poms.

 

[spannerman]

It depends on the state of tune of the engine. A peakier engine with a narrow rev range will benefit a lot from close ratios but wouldnt be as benefitial if the engine has a nice wide torque band. I once had a car gain 3.5 seconds around 1.30 lap , going from an open diff to a welded up unit. The only cost was some welding wire and new diff oil.