What is a camera upgrade?

I think fitting bike carbs is a recipe for pain, they are not designed for cars and unless you do something to the head and cams I doubt much power can be gained.

If you don't want to pay £600 then I would go with a really good service and make everything work perfectly and the exhaust and air filter...it will sound faster and make a small bit more power...maybe. After that, head and cams but probably a Zeta can swap would be more cost effective £ per bhp.

Speed costs I am afraid