The original Q-SPD SD Series began life in 2004 as the ideal alternative to stern drives offering a virtually maintenance free solution to the worlds most maintained propulsion system, stern legs. Nowadays the SD Series is available for power options from 500hp to 2000hp* and installed on commercial and pleasure boats all over the globe.
Construction of the main structural component is by advanced resin infusion techniques, incorporating Eglass and Carbon Fibre reinforcements in an epoxy matrix to produce a light weight and structurally very strong drive system. Composite construction reduces corrosive issues and allows easier maintenance and care.
Due to advanced propeller design, a unique ventilation system, integral thrust bearing and the evolution of the unique twin side rudders, Q-SPD SD Series drives are smoother and quieter than any other surface drive. In fact, reports claim smoother than conventional due to the elimination of cavitation, yet they offer all the performance advantages of a fully ventilated surface piercing propeller. The twin rudders also offer better tracking, steering and maneuverability at all speeds.
By design, the Q-SPD SD drive is compact in length, which means they do not impose on waterline length like other surface drive systems. They offer shallower draft than most other propulsion options, and can be used in single, twin or multiple applications. They are suited to many hull forms including some displacement catamarans and are ideal for both recreational and commercial applications.
The SD Series is a fixed surface drive configuration with a 6º nominal propeller shaft angle and includes an integrated water cooled thrust bearing. Thrust is delivered to the transom by way of the SD drives thrust bearing which is located on the inboard side of the transom so is not susceptible to the the harsh sea water environment. Q-SPD also supply an intermediate drive shaft as standard with all systems to couple the drive to the gearbox, with standard and custom lengths available. Exhaust is used to ventilate the propeller at low speed for faster acceleration and smoother transition, plus there is a built in ventilation system that automatically ensures the propellers are adequately ventilated at all times. With Q-SPD SD series surface drives, there is no need for unsightly holes or grills to be incorporated into the swim platform.
The Q-SPD SD is delivered as a completely assembled system that mounts directly to the transom with all connections to support systems being inboard where it is safe from the elements. Installation is as easy as it gets as is Maintenance. Because there the critical parts are inboard there is no risk of damage from fouling and water ingress is minimized completely. Q-SPD uses highest quality, long life, low maintenance bearings and bushings for all steering and drive line parts and
Q-SPD SD drives should be considered as a most viable alternative to stern drives and conventional underwater shaft systems, where performance and efficiency can be increased and draft reduced, and also as an alternative to water-jets when speed and efficiency are essential.
* – drive system ratings are depending on overall vessel specifications and mission