Ive got a project where I have to reduce the weight of a gearbox,

http://www.ondrives.com/products.asp?recnumber=33

I need to reduce the weight by 1/3 without compromising strength.

I was thinking of changing the material for the actual cogs from high carbon steel to nylon or possibly I was also thinking of the material used in the essex v6 that everyone replaces to steel or ally timing gear.

Does anyone know what that std material is or can lend any help?

thanks

scott