Originally Posted by Equilibrium Tuning
The dyno doesn't measure torque. All it really measures is acceleration of the drums. It then calculates the power required to achieve that acceleration and finally calculated engine torque using RPM data.
Load bearing dynos also measure the load being applie by the eddy brakes and add that back into the calculated power.
Thanks Ed for clearing this up
I was pretty sure that's how the dyno measured power output, by measuring torque applied to the rollers and how quickly it can accelerate them.
Also, I looked through Airboy's posts on his website, they are very informative. It makes sense now seeing it like he put it. The torque bump occurs due to the non-linear function of the rpm vs. road speed curve in an automatic, and how the dyno goes about calculating at what engine rpm a certain torque is made when using the "calculate from road speed" function.