What is the difference between dyno tuning and road tuning?
Dyno tuning approximates driving on the road by placing a load (provided by the dyno rollers) on the vehicle. In general, this load is somewhere around 3000 Lbs., so it does not accurately simulate the actual load (street weight of a Cobra coupe is around 3900 Lbs with driver). In addition, rolling friction is not accurately simulated (the front tires are not rolling), and aerodynamic drag is not taken into account. In general, you will run a bit leaner (A/F ratio) on the road than on the dyno. However, road tuning is not employed by all tuners, and may cost more than dyno tuning. Hermann, owner of HorsePowerByHermann and an excellent tuner, said it best. “The best way to get the tune nailed is to drive and log it the way you use it….on the road. The dyno will NEVER accurately duplicate those conditions found while actually driving the car. The difference is HUGE. Never have I seen a car that was dyno tuned only (and not road tuned) log well on the street. They are always off in one
