fuel consumption

[Qwikcorty]

im just back from a trip to warragul with that new united plus 94, and the DTE is saying 522, and i drove 128km so far on the tank.
So 650km out of a tank for my std au with only tickford snorkle and air scoop.
Would a k/n filter make much difference? and how much would pacemaker tri y's and a good twin system help with economy?

what km's are other people getting with their au v8's?