How to Prevent Turbo Lag

by Renee Booker

Turbochargers can increase horsepower in any engine design, by compressing fuel and air and forcing it into the engine's combustion chambers. This higher concentration of air/fuel creates a more powerful explosion, driving the engine's pistons downward with great force and velocity. There are, however, problems inherent with turbocharger design, with the most notable being "turbo lag." There are many ways this problem has been addressed by various auto manufacturers and after-market parts companies, each with their own unique designs and solutions.

Install a smaller turbocharger. A small turbocharger turbine has less mass, and therefore requires less energy to start and continue spinning than its larger counterparts. This solution has its own pitfalls, however, in the form of less total power output and lower efficiencies at high crankshaft rotations per minute.

Install a smaller intercooler. A large intercooler increases turbocharger lag by increasing the volume of air that must be compressed before reaching the cylinders. In theory, a turbocharger would be most efficient when mounted directly in front of the intake port, only having to compress air in the tiny gap between itself and the cylinder. As things like intake tubing and intercoolers are added in between the turbocharger and the intake port, the turbocharger's work load increases.

Install a twin turbocharger setup. This is the most common way to reduce turbocharger lag and is employed by most automotive manufacturers that make use of turbochargers. This system consists of mounting a small turbocharger in front of a large turbocharger. This system allows the small turbocharger to wind up quickly and in turn, feed compressed air into the larger turbocharger which then forces the now highly pressurized air into the combustion chambers of the engine.

Install an anti-lag system. An anti-lag system is the most advanced system currently employed by racing teams all over the world to minimize turbocharger lag and increase throttle response times. There are many variations of anti-lag systems but the basic concept behind the design is to keep the turbocharger constantly spinning, thus eliminating lag by routing intake air directly into the turbine's exhaust port when the throttle is closed. Fuel is then injected into the exhaust housing where it spontaneously combusts upon coming in contact with the red hot turbine, causing the turbocharger to keep spinning even when no exhaust gas is present due to the throttle being completely closed. This process keeps the turbocharger spinning at all times and keeps the engine's intake passages constantly charged with pressurized air.

About the Author

Renee Booker has been writing professionally since 2009 and was a practicing attorney for almost 10 years. She has had work published on Gadling, AOL's travel site. Booker holds a Bachelor of Arts in political science from Ohio State University and a Juris Doctorate from Indiana University School of Law.