Quote:
Originally Posted by Mike Benvo
3. I have dynoed on dynojets before. This was my first time on a Dynapack and I was surprised to see the numbers. I am no expert on dyno's themselves, but theoretically not having the wheels and tires mounted to the hubs could signify less loss. Someone with more knowledge on dyno's themselves and the differences might be a better resource for this. I only know the tuning and programming stuff  . |
I would personally trust the dynapack more in terms of accuracy and repeatability as they are actual "brake" dynos similar to what we use in the aerospace industry and what auto manufacturers use to develop engines.
From what I understand, dynojets and dynapacks would use very different calculation methods to establish power ratings. I believe overall drivetrain inertia can have much less impact on a dynapack since it is a brake dyno and does not rely on a drum's inertia to load the engine, it all depends how fast/slow the operator sets the acceleration rate. Further, there is also no loss due to tire deformation and slippage at the tire/drum interface. IMO it is normal and expected to see different absolute numbers on both dynos.