Twin Vs. Single Turbo

Turbochargers, or gas compressors that boost engine speed, can be either twin or single turbos.

A turbocharger refers to a gas compressor driven by engine exhaust gas to increase the power and torque of an internal combustion engine. Twin turbos and single turbos can both be used for this purpose, but yield different results.

Lag Reduction

Single turbos are subject to lag, or a time delay between fuel injections used to accelerate air to the engine intake manifold. Twin turbos utilize four engine cylinders for optimal speed; single turbos require all eight cylinders. The twin turbo setup, along with a boost controller (a device that controls the boost level generated by the intake manifold), helps control higher engine speed levels while minimizing lag.

Size

Twin turbos are larger, and therefore consume more engine space than single turbos. Due to their compact size, single turbos also cool better. Single turbos are also easier and less expensive to set up and install than twin turbos.

Power

Single turbos are typically favored for drag racing applications due to their ability to generate maximum boost at greater engine RPM, or revolutions per minute. Twin turbos offer smoother engine function, and are considered better for city driving.

References

• Turbo & High-Tech Performance: The Single vs. Twin Dilemma
• "Turbo: Real-World High-Performance Turbocharger Systems"; Jay K. Miller; 2008

Resources

• "Turbocharging Performance Handbook": Jeff Hartman; 2007