A supercharger and a turbocharger both force extra air into an engine, but they are driven differently: a supercharger is turned mechanically by the crankshaft, usually through a belt, while a turbocharger is spun by exhaust gas flowing through a turbine. That one difference shapes how each delivers boost, how it is packaged under the hood and what it costs the engine to drive it. Neither is universally better; the right choice depends on the vehicle, how it is driven and the rest of the build.
How a supercharger works
A supercharger’s compressor is linked to the crankshaft, so its speed is tied directly to engine speed. Because it never waits for exhaust flow, boost arrives without the spool-up delay associated with turbos. The trade-off is that the engine has to spend some of its own crankshaft power turning the supercharger, which is known as parasitic loss.
How a turbocharger works
A turbocharger has a turbine wheel in the exhaust stream connected by a shaft to a compressor wheel on the intake side. Exhaust energy that would otherwise leave through the tailpipe spins the turbine, which drives the compressor. Boost is usually controlled by a wastegate that routes some exhaust around the turbine, and many diesels, including the 6.7L Cummins, use variable geometry turbochargers that change exhaust flow through the turbine instead. Because the turbo needs exhaust flow to spin up, there can be a short delay before full boost, commonly called turbo lag. A turbo also adds restriction in the exhaust and needs an oil supply, and often coolant lines, for its bearings.
Supercharger vs turbo at a glance
| Factor | Supercharger | Turbocharger |
|---|---|---|
| Driven by | Crankshaft, through a belt or gears | Exhaust gas spinning a turbine |
| Boost response | Tied to engine speed, no spool delay | Needs exhaust flow to spool, so some lag |
| Cost to drive | Takes power from the crankshaft | Uses exhaust energy, adds exhaust restriction |
| Plumbing | Belt drive and intake ducting | Exhaust-side plumbing plus oil feed and return |
| Heat | Compressing air heats it; intercooling is common | Same, plus heat from the exhaust side |
Centrifugal vs positive-displacement superchargers
Superchargers come in two broad families, and they behave very differently.
Positive-displacement: Roots and twin-screw
Positive-displacement superchargers move a fixed volume of air with each rotation, so they can make boost from low engine speeds. On V8s they typically sit on top of the engine in place of the intake manifold. A Roots blower moves air into the intake without compressing it internally, while a twin-screw design compresses air between its meshing rotors and is generally considered more thermally efficient than a Roots unit. Positive-displacement units suit drivers who want strong low-speed response, at the cost of more heat at high boost and a taller package that can affect hood clearance.
Centrifugal
A centrifugal supercharger uses an impeller spinning at very high speed, much like the compressor side of a turbo, but driven by the crankshaft through a belt and a step-up drive. Its boost rises with engine speed, so power builds progressively and is strongest toward the top of the rev range. Centrifugal units usually mount at the front of the engine like an accessory and are often paired with an intercooler. Drivers who prefer a linear, factory-like feel at low speed and stronger top-end pull often choose this layout.
Which one fits your build?
- Driving style: low-speed response for street or towing favors positive-displacement or turbo setups sized for early boost; top-end pull favors centrifugal.
- Packaging: hood clearance, space for intercooler plumbing and exhaust routing.
- Supporting parts: fuel system, cooling, drivetrain strength and the calibration the kit maker specifies.
- Emissions rules: some states, including California, require aftermarket parts that affect emissions to carry an approval for street use. Check your state’s rules and the kit documentation before buying.
For what to realistically expect in output, read how much horsepower a supercharger adds, which explains why results depend on the engine, boost level and supporting modifications.
Supercharger kits we carry
Most of the supercharger kits we carry are ECS kits built around Paxton NOVI centrifugal superchargers for GM V8 platforms, including the C6 Corvette, C5 and C7 Corvette and the Camaro, plus kits for the LS3. Fitment is specific to model year, engine and transmission, so check each listing and contact us if you are unsure.
Compare every kit by vehicle on our supercharger kits by platform page.
Related guides: variable geometry turbos and turbo lag · turbo failure symptoms · what does an intercooler do?.
More guides: supercharger maintenance · supercharger whine vs turbo whistle · is a supercharger worth it? · what is turbo lag? · what does a blow-off valve do? · supercharger kit prices.
Shipping is a flat $80.00 per order to US addresses, with 15-day free returns. Questions? Ask a parts specialist.