Automakers in recent years have been turning to turbocharging as a way to downsize engine displacement and increase fuel economy, while at the same time, those building high performance and racing engines are targeting turbocharging for substantial power gains.
The OEM’s regard GDI (Gasoline Direct Injection) as a key enabler for utilizing turbochargers to downsize the engine displacement. With modern direct injection coupled to variable cam timing, added power output generated by turbo boost is now exploited more fully than before without risk of detonation, yet with significant benefits in fuel economy when running under light load.
As a result, OEM’s are shrinking the displacement of the engine, leading to weight and fuel economy savings. However, when power is required, the turbo kicks in to provide the boost, adopting the feel of a larger displacement engine. Turbos for OEM applications are sized to provide the best combination of low-end torque and peak power.
In the aftermarket, turbochargers are a relatively easy way to significantly increase the power density of an engine.
In simple terms, adding more air and more fuel to an engine will create more power.
Of course, the engine and vehicle systems must be adequately prepared to handle this extra power. Many systems will add an intercooler to reduce intake manifold temperatures and aftermarket ECU to control fueling and ignition. Depending on boost level, consideration for upgrades include (but are not limited to): head gasket, head bolts, clutch, pistons, connecting rods, crankshafts, transmissions and differentials, because all components will be exposed to the rigors of additional power.
Our friends at Garrett put together an excellent explainer video to showcase how turbos work. Watch it here: