of the stator vanes hydraulically to 'performance angle' which permits the converter to achieve stall about 1000 rpm higher than in 'cruise' as well as redirecting oil to strike the next-lower drive turbine which effectively lowers the drive ratio of the transmission and allows engine speed to rise for greater output. Because of its unique operating characteristics, the Turboglide does not require large changes in engine RPM even with very large differences in car speed or desired engine output. In fact, accelerating from rest, the engine speed remains nearly constant (with no movement of the accelerator), even as the vehicle accelerates. The actual engine speed is a function of the pressure applied to the accelerator. One interesting effect during acceleration is the audible transition from the first gear turbine (occurring about two seconds after takeoff with moderate throttle), then progressing through the remaining two turbines which were not so audible. A similar effect occurs with some stepped-gear automatic transmissions, in which the first gear has a characteristic whine not present in higher gears. At full throttle, the Turboglide will maintain the engine RPM within a narrow (~400 rpm) span of speed around 3500-4000 rpm where the best engine output is maintained, and the car will accelerate with a strong slingshot effect to catch up as the ratios drop imperceptibly as the car speed increases along the road. The effect is very similar to that of a jet aircraft during the take-off phase, since the engine maintains a strong high speed and the car accelerates, smoothly and strongly, from rest to maximum. In the normal light traffic driving, the Turboglide automatically selects the highest (the lowest numerically) practical ratio, and the engine speeds run in the 1000-2500 rpm range, saving fuel and improving the throttle response of the car to the small pedal motions. The 'Grade Retarder' range was to provide engine braking when necessary, a driving condition which could absorb close to of power above to what was available via the engine compression, by counter-rotating the turbines in the converter and soaking up the vehicle energy by agitating the oil inside the converter housing. No low range was provided with Turboglide, as in the Drive range the ratio was always automatically and perfectly matched to the requirements of the operator (all ranges being always engaged, low and intermediate would freewheel on the 'sprag-clutches' as needed), and with the Grade Retarder