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What is a Turbo?


Turbo Cross Section - Image courtesy of xspeed.com.au
A Turbo or Turbocharger is a compressor that forces air into the intake. This is done with a turbine that runs off the exhaust gases. This drives the compressor via a shaft that connects to the turbine. It will force an increase in air mass for the combustion stroke. This is a much more efficient way of using forced air induction to increase the power of an internal combustion engine.

Types of Turbo configurations

Single Turbo


Single Turbo
Single Turbo kit for a Ford Focus - Image courtesy of precisionturbo.net
The single Turbo configuration is the easiest to install, least complicated and least expensive of the 3 types of Turbo configurations. You only have to worry about installing one turbo and routing the piping (and possibly an Intercooler) for one turbo. However the down side of the single turbo is turbo lag. Larger Turbos are required to get the same boost as 2 smaller turbos and therefore the added mass of the larger turbines means it will take it longer to spool up and create boost. On the positive side the single turbo is more efficient and more free flowing.

Parallel or Twin Turbo


Twin Turbo Engine
Twin Turbo Engine - Image courtesy of race-dezert.com
A Twin Turbo system uses 2 identical sized turbos usually on V type engines so each turbo runs off of each exhaust manifold. This allows for smaller turbos to be used and this significantely reduces Turbo Lag. Turbo Lag is the time it takes a turbo to spool up and start producing boost.

Sequential Turbo System


Sequential Turbo
V8 Quad Turbo Boat Engine - Notice the smaller turbos under the Larger Turbos, this means this engine is a Sequential Turbo System - Image courtesy of pprune.org
Sequential Turbo systems use 2 different sized turbos. They use a smaller Turbo for lower RPM's and a larger Turbo for Higher RPM's. So at a certain RPM the larger Turbo will take over for the smaller Turbo.

Quad Turbos


Quad Turbo Engine
V16 Bugatti Veyron Quad Turbo Engine - There are 2 more Turbos on the other side of the engine - Image courtesy of www.bugattipic.com
Quad Turbo systems work very similar to a Parallel or Twin Turbo system. They use 4 Turbos of the same size. Usually these types of systems are reserved for V12 or V16 engines. They have the required exhaust flow from 3 or 4 cyclinders.

Variable Vane Turbos


Varialbe Vane Turbo
A good explanation and illustration of a Varaible Van Turbo - Image courtesy of ford-trucks.com
Variable Vane Turbos are larger Turbos that can adjust the vanes that control the amount of air that the compressor turbine forces into the intake. This makes the Turbo act like a smaller turbo at low engine rpm and loads. And when the engine rpm's and or load are high, the vanes of the turbo open up to allow full boost. It also make one large Turbo work much like a Sequential Turbo system.

These Turbos are much more expensive than traditional turbos but they perform extremely well and are great for situations that have limited space. Plus they are much more simple because you get the performance of a Sequential Turbo system but only use one Turbo.

Programs that take Turbocharging into account

We have 3 programs that can utilized Turbocharging when conducting Engine Simulation: Engine Analyzer v3.4, Engine Analyzer Plus v3.4 that use simple inputs and allow for Intercooling as well. And Engine Analyzer Pro v3.9 uses more detailed inputs using a Compressor Map. Engine Analyzer Pro also lets you specify a restriction and an effectiveness rating.

And we have 3 other programs that take Turbocharging into account when making calculations. Compression Ratio Calculator Plus v2.3 calculates Effective Compression Ratio that is used by Supercharger companies to show requirements for boosted engines. And Fuel Injector Calculator v1.1 also takes Supercharging into account.

And if you have a Drag racing car or a Road Racing car with a Turbocharger and want capture your vehicles runs with a data logger we have our Drag Racing Datamite and Road Race Circle Track Datamite v3.7 software that can capture the boost of your Turbo with our Datamite III USB data aquisition hardware.