The six-speed conversion had lost its teeth on the 1st gear gear-set.
Most of the teeth on the freewheeling 1st gear had gone + all the teeth on the fixed mating gear which is unfortunately part of the primary shaft thus entailng a new primary shaft and mating 1st gear set. All other parts survived unscathed and fortunately replacement parts were immediately available ex-stock.
Dave's R42 is a 383 Chevy powered car with Motec managed fuel injection and in the region of 500+ BHP.
We are not experts in this field but consider that a major contributory factor in this failure was a couple of 'miss-shifts' at the debut event a few weeks previous where Dave managed to miss-slot back into 1st at 6K+ from 2nd instead of getting 3rd - twice. Just one of those things, all was ok and lovely in pre-testing but as can happen in the heat of the moment, if it can go wrong, it will and whilst Dave's box survived that shock, it failed at the following event....(remember too that I broke the one and only driveshaft failure ever encountered on Roys 'A11GTD' when I launched off the start line in 4th instead of 2nd - oop's
) Must have surely shocked the teeth on 1st with the 'reverse loading' of engine braking...? even if only for a split second in time.
I would not consider this to be any form of weakness in the supplied conversion, just an operation error and one that could happen to anyone really. Dave tells me the shift and selection is incredibly slick and smooth and is looking forward to the next event.
Oh - and he won his class at Goodwood (again) and was about 10th overall on the day - not bad considering the number of single seaters there....
about a 91 second standing start lap - scary!!