Getting good low rpm data at full throttle with my chassis dyno is difficult at best. Especially with an automatic transmission. My dyno is a eddy brake dyno with smaller rollers (low inertia). My engine dyno does a much better job at this.
i learned on a clayton chassis (eddy brake) and while it was consistent, low rpm was tricky. don't get me wrong, it was great for tuning and driveability issues as well as full pulls.