Quote:
Originally Posted by bandit86
Bullydog tech support says the truck gets better mileage on performance setting. Anybody have a real life experience that proves that? Doesn't sound right
|
People on the VW TDI sites will make the same claim, but there are too many variables and too little actual testing to verify. As far as I know the turbo diesel piggyback boxes can only affect fuel pressure and injection timing, so I doubt very much that engine efficiency can be changed in any meaningful way. But if the factory injection timing is conservative to allow for use of low cetane fuels, some advance with good fuel may improve fuel mileage.
The VW folks are in the habit of replacing injectors and turbos, so those can certainly make a difference as well, but the way they drive afterwards negates any potential benefit.