AEM have released a mobile dyno that you fit to your car and which then allows you to drive around to measure the power of your engine.
No specials facilities required. Bolt it onto your car and forget about it while getting real world power figures, all the time (awesome).
AEM’s Dyno-Shaft Sportsman on-vehicle dynamometer system is literally a dyno on your car. It is as accurate as the most respected dynamometers in the industry. It provides real, accurate Horsepower and Torque numbers that are produced by measuring a vehicle’s Torque and RPM at the driveline, while you drive! The Dyno-Shaft Sportsman Series is designed for competitive amateur racers and serious performance enthusiasts whose applications can utilize a cast iron slip yoke. For higher stress applications, the Dyno-Shaft Pro Series kit features a CNC-machined Chrome Moly slip yoke.
Is this something you would use?