The G-Lader is a

scroll-type supercharger The scroll-type supercharger is a scroll compressor used as a positive displacement orbiting-spiral supercharger. It is a compromise between the more rugged rotating lobe, and the more efficient sliding vane type superchargers, and is considered t ...

used in various Volkswagen Passenger Cars models. Its purpose is to increase the motive

power Power most often refers to: * Power (physics), meaning "rate of doing work" ** Engine power, the power put out by an engine ** Electric power * Power (social and political), the ability to influence people or events ** Abusive power Power may a ...

output from the

internal combustion engine An internal combustion engine (ICE or IC engine) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal c ...

attainable with a given

engine displacement Engine displacement is the measure of the cylinder volume swept by all of the pistons of a piston engine, excluding the combustion chambers. It is commonly used as an expression of an engine's size, and by extension as a loose indicator of the ...

. Since it is not enough to simply inject more fuel, as this produces too rich an air-fuel mixture, more intake air has to be added at the same time. This can be achieved with an exhaust-driven

turbocharger In an internal combustion engine, a turbocharger (often called a turbo) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake gas, forcing more air into the engine in order to pro ...

, or a crankshaft-driven positive displacement compressor. The G-Lader is in the compressor category, since it is crankshaft-driven and does not have the "lag" usually associated with turbocharged engines.

History

This type of air pump, notable for low noise and high efficiency, was patented on 3 October 1905 by Léon Creux of

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

( US Patent 801,182). Due to the very imprecise production methods of the period, however, it was not manufacturable for a long time, since the displacer (described below) inside the compressor comes within tenths of a millimetre of the housing wall without making contact. Only with the more advanced engineering methods of the 1980s, did it become possible to produce the G-Lader. Contrary to expectations, Volkswagen's designs turned out to need relatively frequent repair in normal operation, which was one of the reasons why that manufacturer eventually abandoned this technology at the time. The main cause of its relatively high failure rate was that Volkswagen misrepresented the G-Lader as maintenance-free. Depending on RPMs, load, and design details, various parts wear out, with results ranging from impaired performance, to destruction of the G-Lader. Yet it is frequently possible to extend the life of the G-Lader, sometimes to several hundred thousand kilometres, by periodically overhauling it with suitable replacement parts.

Operation

The supercharger housing holds what is called the ''displacer plate'' (or just ''displacer''), on both sides of which are

spirals In mathematics, a spiral is a curve which emanates from a point, moving farther away as it revolves around the point. Helices Two major definitions of "spiral" in the American Heritage Dictionary are:seals between the latter and the housing. The housing itself also has spirals on both sides that mesh with those on the displacer. Driven by the crankshaft, which is connected to the ''displacer shaft'' by a small belt, the displacer moves eccentrically with respect to the supercharger housing (like the rotor in a

Wankel engine The Wankel engine (, ) is a type of internal combustion engine using an eccentric rotary design to convert pressure into rotating motion. It was invented by German engineer Felix Wankel, and designed by German engineer Hanns-Dieter Paschke. ...

) and, through this motion, forces the intake air into a smaller and smaller space, ultimately producing a maximum

gauge pressure Pressure measurement is the measurement of an applied force by a fluid ( liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pre ...

of with standard delivered pulleys.

Sizes and car models

The German name ''G-Lader'' comes from the shape of the supercharger (german: Lader), which looks like the letter G. The displacer's spirals are either deep or, in the larger version, deep, i.e. close to 60 mm. This is the reason we see the engine designations G40 and G60 in the names of Volkswagen models in which it was used: * Volkswagen Polo Mk2 GT G40 (''Typ'' 86c - Limited to 500 vehicles first series (all black, fog head lamps) and a second of approx 1500, standards colors plus 500 all black for French market only) * Volkswagen Polo Mk2F GT G40 (''Typ'' 86c) * Volkswagen Golf Mk2 GTI G60 (''Typ'' 19E) * Volkswagen Golf Mk2 G60 Rallye (''Typ'' 19E - limited to 5000 vehicles) * Volkswagen Golf Mk2 G60 Limited (''Typ'' 19E - limited to a special Volkswagen-Motorsport series of 71 vehicles) * Volkswagen Corrado G60 (Corrado - ''Typ'' 53I) * Volkswagen Passat (B3) G60 Syncro (Passat - ''Typ'' 35I)

References

* * * {{VW Superchargers Volkswagen Group engines

History

Operation

Sizes and car models

See also

References