It looks like an inertia dyno. I made one myself in the past three month. But few problems I am having with this type of dyno is

1. How do you determine the state of tune of the engine on the dyno? If the engine is mounted onto the dyno it may not be running at maximum output condition (due to needle setting.)
Do you tune it on your car and then mount the engine to the dyno?

2. How do you control the throttle opening? Most of the time, this is done either through hand or the transmitter? But the speed at which you open the throttle will influence the acceleration?

3. Cooling. Do you need to attach a fan to the dyno?

Hope somebody can help me on this!!