just installed a edelbrock performance carb on my sons Z400 wow what a difference it made on the bottom end power of the quad in fact it made more power thru the whole powerband. Well worth the cost and time it took to install.

 

what size is the carb and what other mods are done to it?

 

It was made for a predator 500 so it is 36mmX40mm oval throat carb. quad has no air box open K&N filter ESR full pipe and hot cams stage 1. stock piston and bore he can beat most stock 450s can keep up with some modded 450s. A big plus for him is he only weighs 127 lbs soaking wet. When it is time to rebuild it we will big bore it unless we can afford to buy him a 450.