It used to be that when the conversation turned to superchargers, you'd immediately start having visions of a monstrous, fully polished 6-71 blower-replete with dual quads-poking defiantly through the hood of a nasty street machine. Add to that the large pulleys conveying a 3-inch wide belt with its ever-so-distinct whine, and the fact that the driver had to take right turns with extreme caution due to the aforementioned appendage blocking his vision, and you had a pretty clear picture of one awesome street beast. But that was yesterday, and looks aren't always equivalent to performance.
While that archaic air mover is still available today for those who want it (and those machines that can get away with running it), there's a whole new generation of superchargers that are small, quiet, and discreet-almost tailor-made-for today's high-tech vehicles. To the untrained eye it could easily be mistaken for just another engine accessory. Technology has advanced so that bolting on a supercharger can be almost as simple as swapping a carburetor and intake, and with the progress of electronic fuel injection and computer control, the engine merely "adapts" to its new conditions and goes along with the improved performance. In addition to that, many of the new superchargers are smog-legal.
The Basics Defined
Let's take a look at how a supercharger works. In order to operate, the engine needs a mixture of air and fuel. The mixture is burned and the leftovers leave the "pump" in the form of exhaust gasses. Increasing the amount of air and fuel the engine can gulp down increases its power output. However, on a normally aspirated engine, even after the cam has been changed, the carburetor has been swapped, and the heads ported, there's still a limit to how much air and fuel it can take in. Increasing the engine's displacement can improve things, but again, there are limits. A supercharger is a pump mounted in the intake stream of the engine, and driven by the crankshaft. When operating, it pressurizes the air going into the engine, forcing more air and extra fuel-via a recalibrated fuel delivery system-inside the cylinders than normally could be ingested. The end result is that with the increased amount of air and fuel inside the cylinders, the engine makes more power, because it's now "acting" larger than it really is. One of the huge reasons why blowers are so popular is because they're more forgiving than a big nitrous system, and they don't require all of the creative exhaust plumbing that a turbocharger does, nor do they generate as much under-hood heat.
One company that has capitalized on the new supercharger market is Whipple Supercharger Systems in Fresno, California. With their patented screw-type blower design, they have created a niche for themselves in the world of under-hood power enhancers. One particular area of the supercharger market that is steadily growing is trucks and SUVs. One of the reasons for the growing popularity of supercharged trucks is that; although you can buy a brand new truck complete with big block, they just don't have what it takes to haul a fully loaded trailer with any confidence up a steady grade. That was the dilemma that the owner of this '98 Chevy 3500 Crew Cab, faced. While the truck's 7.4-liter Rat had more than enough power around town, it was a complete slug with a full load connected to the hitch and mountain roads on the horizon.