Supercharging Basics

When it comes to squeezing more horsepower out of a given number of cubic inches, nothing compares to forced induction. The amount of power any engine produces depends on how much air/fuel mixture is pumped through it in a given instant of time.

Therefore to increase the engine’s power output, you have to either
1. Increase the engine’s displacement (more cubic inches),
2. Increase rpm
3. Increase breathing efficiency or cylinder filling (called “volumetric” efficiency).

Engine speed naturally goes up when the throttle is opened, so for an engine of a given displacement the fastest route to more power is to increase its volumetric efficiency. A bigger throttle body, a better flowing intake manifold, a cam with more lift/duration/overlap, opening up the head ports and bigger valves are all traditional means by which an engine can ingest and pass more air and fuel. But even the best built naturally aspirated engine will never achieve 100 percent volumetric efficiency because atmospheric pressure can only do so much to overcome the restrictions and turbulence in the intake system. And as engine speed increases, volumetric efficiency drops off.

The only way to overcome this limitation is to add a forced induction system. By mechanically increasing the volume of air that enters the engine, forced induction in effect increases atmospheric pressure giving the air more “push” as it enters the cylinders. Volumetric efficiency goes up and the engine makes substantially more power. Now the engine can breathe at 100 percent volumetric efficiency or higher depending on how much “boost” is built into the system. Crank up the boost pressure and even a little engine will come to life. This is why many of the major OEM manufacturers like BMW, Mercedes, GM and Ford are now downsizing engine capacities and using forced induction to lift the power and torque output to equal or surpass larger naturally aspirated capacity engines.

Why Supercharging?

The primary advantages of supercharging over turbo charging are instant throttle response and more boost at low engine speed. Because a supercharger is belt driven off the crankshaft, it can deliver boost the instant the throttle is opened.

There are two main types of Superchargers:

1. Positive Displacement (includes Roots and Screw Superchargers) – these deliver a fixed volume of air for each revolution. This means that maximum boost is available from low in the rev range and holds all the way to the engines maximum rpm. There is no lag and the engine delivers instantaneous power and tremendous low end torque.

2. Centrifugal – these deliver boost in a linear fashion in relation to engine speed– the faster the engine speed the more boost pressure is produced. This type of Supercharger gives a very smooth OEM feel to the power delivery.

A bolt-on supercharger can add anywhere from 30 to 200% more Power and Torque to an otherwise stock engine.

The other main factor to consider is fuel efficiency and emissions. With an increase in low down Power and Torque, the engine does not have to be worked as hard to give the same performance as a naturally aspirated engine. This means less fuel is used and the engine is less stressed due to the lower engine rpm.

Supercharge your vehicle with a Bullet Supercharge System

Superchargers are currently used as factory fitment to vehicles made by Bullet, BMW, Ford, Holden, Jaguar and Mercedes to name a few; to greatly enhance the power of small capacity engines in their sports models.

For those of you who have been used to Performance Cars – get that High Performance Feeling by installing a Bullet Supercharger.

With over 12 years experience in the installation of superchargers to Toyota V8 engine powered Bullets, you can be assured of attention to detail and engineering expertise when fitting a Bullet supercharger system to your vehicle.

Supercharging will result in the following:

• Substantial increases in power and torque – gains of over 100% can be safely achieved.

• Improved low down performance for towing, hill climbing and off road operation in four wheel drives.

• Dramatically improved acceleration.

• Improved fuel economy under normal driving and most towing conditions.