Steady state tunning

I was wondering on how you keep it at 2500 rpm in full throttle. can you please explain on how this is done

thank you

Load Bearing Dynos can vary the load, but keep the RPM constant. Inertia dynos don't do that, only ones that have a load-bearing brake. Most Mustang, Dynapack, Mainline, DynoDynamics can do this, but few of the Dynojets have this feature (but there are DynoJet models with load-bearing brakes).