Dyno tuning - Performance means nothing without measurement
Laptop adjustments (no dyno)
Some Dyno videos in action: //s782.photobucket.com/user/RianV8/media/DYNO%20TUNING/010.mp4.html?sort=6&o=4
Dyno tuners all differ with their output figures, but how it works is the same. The car is strapped down so it cannot move laterally or longitudinally with non-driving wheels choked on 2-wheel drive dynamometers. On a 4 wheel drive chassis dyno, the distance between the front and the rear sets of rollers can be changed to cater for dyno tuning different wheel based cars.
Front wheel drive cars tend to be more unstable on a dyno than RWD cars, so when dyno tuning FWD cars, small "trainer wheels" are locked into place either side of the front wheels.
A large fan is placed at the front of the car to cool the radiator and any other heat exchangers located there. The dyno tuner sits in the driver's seat and operates the accelerator, clutch and brake. The steering wheel does not need to be touched. The dyno tuner controls speed and other factors via a hand-held pendant that contains controls for load.
The simplest test is a power pull. The 'ramp speed' (rate at which the dynamometer let the engine speed increase) is set and the car is run at very low rpm in the selected gear. Any gear can be used, but second, third or fourth gears are usually selected. The higher the gear the lower the tractive effort trying to pull the car off the dyno. Very powerful cars therefore must sometimes be tested in the higher gears, although second gear is most commonly used.
The load Dyno is also a great instrument that can be used for fault finding and a couple of other engine problems were the car needs to be driven, by driving it on the Dyno for fault finding gives the operator a much easier and safer method of off road fault finding and that also means that the vehicle doesn't have to Dynode at 6000 rpm levels.
The Spitronics ECU is adjusted to a near 100% setting, we then start driving the vehiecle under load on the dyno machine and uses 3rd gear to start adjusting. While under load the Lambda sensor readings are used to fine tune the air/fuel mixture. After that we also take time in checking the ignition timing under various rpm's just to make sure that we get optimal performance without the engine overheating or running too lean. While checking the timing under load, the Lambda readings are also monitored again.
The Pictures bellow shows how the load on the dyno stresses the weakest link. The weakest part usually breaks under load.