PackardV8 wrote:FWIW, engine dynos which simulate and repeat various track loads have been around for 40 years that I know of. Ford used full-scale dyno load runs for their mid-60s Indy development, where engines simulated the full 500 miles of acceleration, decel and pit stops. In the late 60s-early 70s Le Mans efforts each shift was simulated for the full 24 hours.
F1 actually data logs and loads each driver's track test sessions. Once a new engine parameter has been established on the dyno, it can be transfered and repeat the run virtually to see if it adds speed/subtracts time at various points on any of the tracks. Only if it shows promise is the actual full race length dyno run.
The ability of this inertia-dyno to perform simulated laps, drag race runs, etc. is a secondary function of the machine. (Secondary in design, not ability.) The main purpose of the inertia dyno is to have the ability to precisely record the engine's actual accel-rate and to repeat within 0.5%. This provides the engine specialists with the best data to evaluate components/combinations, etc. On-track simulations are continually being tested; however in most cases will be customized for each individual customer's needs.
The F-1 dyno's are very impressive, but also come with a pretty impressive price-tag. (Fully equipped are well into 7-figures!) And the F-1 dyno's are still the "absorber" type (electric) - and have their limitations. As one of the top NASCAR chief engine-builders told me - "they are not perfect and have their issues!" (Referring to the computerized, AC dyno's.)