Dyno Types and how it affects tuning.

Hi Andre and forumers,

For most part of the world there is 2 main dyno types,the inertia (Dynojet/Dynomite) and the other is load bearing dyno (Dyno dynamics/Mainline).

In on of your webinar,you said that the inertia dyno rate of acceleration is affected by how much power the engine make,which i agree,as more power it will accelerate the rollers more quickly,more power and torque is shown on screen. i think this also replicates what the car do on the road (more power and torque = faster acceleration).

On the load bearing dyno,the rate of acceleration is fixed,so the more power the engine make,the load cell will detect it and translate it into torque value.

My question,will this different type of dyno give different end result to our tune especially on the ignition timing numbers? 90% of my tune is on a load bearing dyno,however when i go to inertia dyno on some occasion,i can see that the end result is a little different,i can add 1 or 2 more degrees timing on inertia dyno without coming into knock compare on the load dyno.

And why the numbers between both dyno does not agree with each other?

Thanks