Yes and no.
There are many makers of chassis dynos in the world, Mustang, Dynojet, Superflo, Dynapak, and countless others. Most display within 2-8 percent of each other, but the dynojet always seems to display as much as 20% higher.
I am unsure of the reasoning behind it other than marketing.
The key to keep in mind is that your gains are going to be relative to the machine that you had baseline your car on.
Basically if you make changes to your car and wanted to see the results, you should go back to the dyno that you had made your previous testing on.
You may have made more power, but if you baselined you car on a d-jet then bring it to another shop with a different brand of dyno you make have less power displayed to you. Even though the car is notable more powerful.
Repeatable testing is about control. And the dyno is your control.
Our Dyno has what is called an eddy current load control, It actually take into account the weight and drag coefficient of the car. It also allows us to do other testing like standing start acceleration. 1/8 and 1/4 mile passes. If the weight and the drag coeifficient is entered in the computer correctly the car will run on the dyno what it runs at the track. With the exception of 60ft. Traction is the only limiting factor. It's amazing to get e.t. slips that are that close from the dyno. They're are usually within less than a tenth of what the car does at the track.
But I have done testing on our dyne of cars that have 60ft of 1.37 at the track, and they do the 1.39 on the dyne.
