That you're a wren dealer?

All jokes aside, i think Sara really has a point. The problem is finding an institution with which all manufacturers are willing to cooperate (also those who are knowingly cheating their numbers). The GTBA is a great point for reference, it's just nothing that has any influence on ads....
Also, a "test engine" can be selected so that it will accually produce great figures, whilst many of the production engines come not so close to these values....
Because of the "small" number of turbines sold compared to cars, i guess there is just no large economical interest in getting law enforcement on this subject...it remains in the hands of customers to see wether their product of choice is superior or not, or if they have reason to send it back to be re-worked to specs or given a refund....