Abstract: An adjustable chassis dynamometer includes a fixed roller, an adjustable roller that moves with respect to the fixed roller, and at least one sensor that detects a rotational speed of the fixed or adjustable roller. A belt drive synchronizes rotation of the rollers. The belt drive includes a fixed pulley associated with the fixed roller, an adjustable pulley associated with the adjustable roller, and a tensioner pulley. A belt is provided with an inner surface and an outer surface, and surrounding the fixed, adjustable, and tensioner pulleys, such that each pulley engages the belt's inner surface. The belt drive further includes an idler pulley that moves with the adjustable pulley, is located outside of the belt, and engages the belt's outer surface.

Abstract: An adjustable chassis dynamometer includes a fixed roller, an adjustable roller that moves with respect to the fixed roller, and at least one sensor that detects a rotational speed of the fixed or adjustable roller. A belt drive synchronizes rotation of the rollers. The belt drive includes a fixed pulley associated with the fixed roller, an adjustable pulley associated with the adjustable roller, and a tensioner pulley. A belt is provided with an inner surface and an outer surface, and surrounding the fixed, adjustable, and tensioner pulleys, such that each pulley engages the belt's inner surface. The belt drive further includes an idler pulley that moves with the adjustable pulley, is located outside of the belt, and engages the belt's outer surface.

Abstract: A method and apparatus for automatic tuning of fuel injected engines includes an air-fuel ratio sensor, a load device for controlling engine RPM, a digital computer and a display device. The digital computer displays a plurality of throttle positions to an operator who sets the throttle of said engine to correspond to said display of throttle position. The digital computer varies the engine RPM over the operating range of the engine to determine corresponding map values for storage in an injector signal modifier.

Abstract: A dynamometer for a snowmobile includes a pair of driver wheels which replace the tension idler wheels so as to contact the inside of the snowmobile track. The regular snowmobile tension idler wheels are removed, and the driver wheels are positioned on the idler wheel axle. In the alternative, the dynamometer is attached to the existing tension idler wheels by a coupling plate. In the alternative embodiment, the tension idler wheels are configured for power take off by including pins forming a quick connect coupling mechanism. The quick connect coupling mechanism permits the dynamometer to be connected to the snowmobile without having to remove and replace the tension idler wheels with a different pair of driver wheels. A jack is provided to lift the snowmobile track clear of the ground by applying a lifting force between the ground and the tension idler wheel axle. The dynamometer and jack are integrated so as to share common components.

Abstract: A variable Venturi slide includes a beveled edge at an oblique angle to lower surface of the slide and air flow, and an auxiliary hole having an opening on the beveled edge communicating between the air flow and the interior of the variable Venturi slide. By being located on the beveled edge, the opening of the auxiliary hole is effectively kept out of the high velocity low air pressure air stream at lower air velocities during partial throttle conditions. The auxiliary hole bleeds vacuum from the interior of the variable Venturi slide, picked up by the other lift hole located on the bottom of the slide, and slows the slide lift rate. The slide stays down or rises very slowly under conditions in which a conventional prior art slide would be starting to rise at a linear rate. At higher air velocities, when the throttle plate is opened quickly or operated at near wide open conditions, the opening of the auxiliary hole adds vacuum to the interior of the slide, and increases the slide lift rate.