What You Need to Know About Supercharging a Silverado

When the term dragon is mentioned, most people imagine a massive, scaled flying creature that has the power to melt rocks via fiery-breath. A supercharger is not a mythical creature, but I do consider it a mechanical dragon of sorts – one that breathes powerful compressed air as opposed to red-hot flames. And just like a dragon perched on a mountaintop surveying the land below, the Roots-style supercharger that is most commonly used on a Silverado sits atop the engine in the place of the intake manifold, ready to feed the aluminum beneath it.

Driven by a serpentine belt off the crankshaft pulley, a supercharger is basically a massive air compressor. Its job is to compress the incoming air above atmospheric pressure (often referred to as boost – 1 psi of boost means the air has been pressurized 1 psi above atmospheric levels) before routing it to the combustion chamber. Being pressurized means there are more oxygen particles per litre of air, thereby more fuel can be mixed and the result is more power produced. However, during the compression phase, the intake air does heat up, which is not desirable. The solution to this is to send the air, after compression, to an intercooler where the inlet air can be cooled prior to reaching the intake manifold and entering the combustion chamber.

What is really neat about the Roots-style supercharger kits available for 4.8L, 5.3L, 6.0L and 6.2L Silverado pickups is that all of this is packaged into one assembly. The supercharger, intercooler and intake manifold are all integrated into one system, installed atop the cylinder heads like a traditional intake manifold would. The supercharger itself is based off an Eaton TVS charger, which is a twin-screw design. Available in a variety of displacements, what separates the TVS from other twin-screw chargers is the lobe design. TVS chargers use a 4-lobe design that features a 160-degree twist - traditional twin-screw superchargers feature a 3-lobe design with only 60-degrees of twist – and without getting too technical, the result is a supercharger with increased volumetric capacity, better efficiency and thermal characteristics, all of which combine to produce more horsepower, torque and even fuel economy.  

Working on the principle as described above, superchargers are able to significantly boost the horsepower and torque output of that small-block found in any Silverado pickup truck. Furthermore, because the supercharger is connected directly to the crankshaft pulley via a belt, any time the engine is running, the supercharger is working. This means throttle and boost response is always instantaneous and linear across the entire RPM range. There is no lag or delay for the compressor wheel to spool up – which can often be the experience when dealing with a turbocharged engine.

In real world terms, the extra power and torque will make pulling heavy trailers and the like much easier with less throttle input required. And of course there is always the never-gets-old feeling of mashing the throttle and hurtling forward at a meteorite-like rate. A supercharged Silverado is perfectly happy hauling to the limit or simply putzing around town. One important change when running a supercharger is that you will need to run premium gas all the time. Failure to do so will likely cause detonation.

All of the available Gen IV and Gen V small-block Silverado supercharger systems incorporate Eaton’s TVS technology. That said, not all aftermarket systems are the same. Each manufacturer is responsible for coming up with their own proprietary intake and intercooler design, boost management, fuel requirements and engine tuning.

Some systems come with an included ECU tuner whereas others don’t. Properly tuning the ECU is extremely important in order to properly handle the new air and fuel parameters. An improper tune (or no tune at all) is likely to cause catastrophic damage. Kits that come with a tune take care of this and are ideal for most work and play drivers. Owners that like to thrash their truck a little harder and want to wring out every last bit of performance will likely want to go the custom tune route and would be better off ordering a supercharger system that does not include one.

One other notable aspect to highlight is a bypass system. Some of the TVS-based Silverado supercharger systems are now coming with an integrated bypass system. This bypass circuit will prevent any positive pressure build-up when driving in a low load or high vacuum situation (light throttle cruising, engine at idle or throttle closed and truck decelerating), significantly reducing the parasitic draw of the supercharger when boost is not needed. A bypass circuit such as this is not to be confused or compared with a wastegate – the bypass system provides no boost control under load. The supercharger will always reach and maintain peak boost as needed. This is a nifty feature that helps bolster fuel economy without any sacrifice in performance.

Supercharger displacement, pulley ratio, fuel delivery and tuning capability are all important variables on the overall performance of the supercharger package, and each manufacturer likely has a different idea and setup of how to go about it. Think of it as a rib fest: everyone is cooking ribs, but they way they do it and the ingredients in use produce a unique flavor.

This largely depends on which system you are looking at, but even entry level Silverado supercharger systems are good for a minimum 40% increase in horsepower and torque over stock, equating to an approximate gain of 100-125 horsepower. More aggressively engineered systems that produce higher boost levels can reach up to a 70% increase in power, making over 500 ponies available on tap.

Good news here. The answer is yes. Yes, you can install a roots-style supercharger on your half-ton Silverado at home in the garage. Surprisingly, despite all the bits and bobs that come with any Silverado supercharger system, no real specialty tools are needed. Just a complete set of sockets, wrenches, screwdrivers and a day or two of time is all that is needed to get the job done.