Vr6 Tuning

[AudiA8Quattro]

Just my 2p's worth - any VR6 will need a small refinery to fuel it, especially if you like the loud pedal 

A heavily tuned 16v will also drink fuel 

If a 16v and a vr had the same bhp the vr will always drink more fuel.

Not necessarily. A tuned up 16v which matches the standard vr will probably be just as thirsty.
I was pointing out that any heavily tuned engine will drink fuel.

[Wayne]

Just my 2p's worth - any VR6 will need a small refinery to fuel it, especially if you like the loud pedal 

A heavily tuned 16v will also drink fuel 

If a 16v and a vr had the same bhp the vr will always drink more fuel.

Not really, the VR has a lot more torque so will sit in higher gears whilst the 16V will be screaming along, don't think their will be much in it to be honest.

[AudiA8Quattro]

Also, to add, state of tune has alot to do with fuel consumption.
Engines are set up to run close to lambda, or in other words perfect fuel/air mixture.
This however can be set 10% either way of lambda from factory. I most cases from factory, engines can be set on the lean side, to keep fuel consumption and emissions down.
A re-map will obviously change this.
Other factors will affect fuel consumption, how well the engine 'flows' ie. filter and exhaust, and longer duration cams.
Bigger capacity does usually mean more fuel consumed. but its not always the case.