Weight of components is always a problem when using 'commodity' parts in a car like the Elise. Tradeoff between cost and engineer design wishes.
I have no doubt that a gearbox builder like Quaife could do a box that's 1/2 the weight, but unfortunately (looking at their prices) it would probably end up costing very serious amounts of money (think upwards of $9000 for a gearbox)
Bespoke parts cost money.. How light can you afford to make the car
Bye, Arno.