Australian gearbox gurus Pfitzner Performance Gearboxes (PPG) have completed their first Nissan GT-R GR6 gearbox upgrades in the form of a drop in first gear replacement. You can see it pictured about sitting next to a standard GR6 first gear.

You can tell just by looking at this picture the basics of this upgrade, a much wider gear to increase strength. The main cause of gearbox failures occurs on the teeth of the first gears after extreme stress. Initially fractures develop and eventually teeth give way. Once one tooth is gone the rest follow like dominoes.

To follow on from this, PPG plan some gear upgrades for big horsepower cars as well as a 1st through 4th gear upgrade set.

Link: PPG Home Page
Source: Titan Motorsports via NAGTROC