The numbers by Mustang and DynoJet are company specific. There was a decent article in HotRod recently on the history of DynoJet.
Comparing one dyno to the other is fruitless. Dynos are for tuning devices. Get a baseline, add your parts, then tune for the best numbers. Whether you tune on a DynoJet or Mustang doesn't matter, as long as when you tune, you stick with the same dyno. I'm no expert, but I think we all know dynos are for bragging rights, no matter the chosen dyno.
Additionally, not all manufacturers use the same dyno, in fact most use a braked dyno directly from the flywheel, producing the "BHP" or "Brake Horsepower" number they advertise with.
http://hotrod.com/thehistoryof/113_0...t_chassis_dyno
Wanna test your mods? Hit the track.
