Supercharger Everyone involved in the engine industry today must be completely familiar with the advantages of turbocharging. The simple turbocharging concept has served us well for two decades, the advantages are far from overwhelming, and it is by no means clear that turbocharging will be the favoured method of increasing aspiration density in the future. The principal advantages of supercharging compared to turbocharging include:

• More direct linkage between engine output and operator demand.
• Minimum exhaust-side thermal inertia.
• Minimum under-bonnet heat.
• Smaller size and easier packaging in many applications.
• Potentially lower cost through the avoidance of special materials.

Design

At Turbo Technics, we took the view that package size, weight, and fuel economy are of paramount importance in our market, and for these reasons we chose to develop the centrifugal supercharger.

The key to this design is a planetary traction drive relying on friction between rolling elements to provide the drive force. This approach offers the benefits of :

• Very compact packaging, with minimum length and profile.
• Low weight.
• Low noise.
• High efficiency, particularly at cruise conditions.

A considerable volume of investigative work has been carried out over the years on the subject of traction drives. As applied to the Turbo Technics supercharger, we have 3 "Planet rollers" rotating around fixed axes, supporting a "Spindle" at the centre. The "Drive annulus" is a flexible ring, which is deformed elastically to provide a clamping force on the rollers and hence on the spindle. The compressor impeller is mounted on the spindle.

Result

On a Rover 1.8i engine, an increase in power from 118 bhp to 191 bhp is achieved with a considerable broadening of the usable power band and an increase in torque of 33% at 4,000 revs/min. The resulting performance characteristic suits high power lightweight vehicle such as the Lotus Elise extremely well.

Turbo Technics other lead programme was the application of the supercharger to the American Rotorway Executive helicopter engine, to provide altitude compensation. The helicopter uses a vertical shaft 4 cylinder boxer engine of 2.4 litres and the design brief was to maintain sea level power to 7,000 ft altitude. The vertical shaft engine dictated the use of a vertical supercharger, with seals similar to those used on Formula One crankshafts.

Current development work is aimed at reducing both the size and the weight of the supercharger and body envelope packaging dimensions of approximately 132 x 105 long can be achieved with a unit suitable for engines up to approximately 250 bhp, with a weight of approximately 3.7 kg. A more technical presentation is available here

PLEASE NOTE: Commercial enquires are welcome, however this supercharger is not yet available to purchase as an individual item.