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Engine Components

Flywheels / Balancers / Pulleys

Our theory.

1. Lightened Flywheel.

A lightened flywheel can have a great effect on vehicle acceleration. Rotating components store rotational energy. Reducing the mass (or more correctly "moment of inertia") of these components leaves more of the engine's output to accelerate the car.

The faster a component rotates, the greater the amount of rotational kinetic energy being stored in it.

The stock MG B Flywheel weighs 8.8 kg., our Lightweight CrMo Flywheel weighs 5.5 kg. and the competition CrMo Flywheel weighs 5.1 kg.

2. Heavier Crank pulley.

It may seem counter -productive to hang a heavy chunk of metal on the front of the crankshaft, but a quality racing crank damper will actually produce horsepower and help your engine live longer. The twisting forces imparted on the crankshaft should also be reduced.

The stock MG B Balancer is cast iron (18 tonne) and weighs 1.4 kg., our new MG B Crank Balancer weighs 2.1 kg. and is made from low carbon steel billet (40 tonne) and Zinc Phosphate coated.

Is it not better to have a heavier balancer with a lighter flywheel than a tin pulley (balancer??) combined with a heavy flywheel??
Surely the latter would tend to amplify the twisting forces on the crank - end to end.

Our thoughts:

It has always puzzled us why manufacturers introduce a mass to absorb (damp) the torsional vibration of the crankshaft and then cut a groove to run a vee belt.

Would this not impede the dampening mass from vibrating at its own frequency??

Our pulleys/balancers utilize a solid drive from crank to belt pulley with the dampening mass operating independently and unimpeded.

The mass should be able to vibrate at it’s own frequency, independent of drive belt tension.

Over time, the energy dissipating (rubber/clutch/fluid) element can deteriorate from age, heat, cold, or exposure to oil or chemicals. Unless rebuilt or replaced, this can cause the crankshaft to develop cracks, resulting in crankshaft failure.

3. Multi vee crank pulley.

We use multi-vee belts to drive our supercharger kits due to their improved efficiency compared to conventional vee belts.
The increased surface engagement allows for increased horsepower per inch of belt width compared to standard V-belts.
The added flexibility of a wider but thinner belt offers an improved efficiency, as less energy is wasted in the internal friction of continually bending a thick belt. In practice this gain of efficiency causes a reduced heating effect on the belt. A cooler-running belt has a longer service life.
The improved transmission ratio (Poly V® = 1 : 60 vs V belt = 1 : 20) of the belt minimizes slip, hence heat reducing load on the engine, resulting in potential increased fuel economy and available power.
It has been suggested this could be worth 2-3 hp on a 4 cylinder engine.