G-Lader

An animation of the operation of a scroll-type supercharger. Air is confined between the two spirals and is compressed as it is forced towards the centre. In automotive application, the spirals would have far fewer turns.

TheG-Laderis ascroll-type superchargerused in variousVolkswagen Passenger Carsmodels. Its purpose is to increase the motivepoweroutput from theinternal combustion engineattainable with a givenengine displacement.Since it is not enough to simplyinject more fuel,as this produces too rich anair-fuel mixture,more intake air has to be added at the same time. This can be achieved with an exhaust-driventurbocharger,or acrankshaft-driven positive displacementcompressor.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 highefficiency,was patented on 3 October 1905 byLéon CreuxofFrance(US Patent801,182).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 highfailure ratewas that Volkswagen misrepresented the G-Lader asmaintenance-free.Depending onRPMs,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 periodicallyoverhaulingit with suitable replacement parts.

Operation

A G-Lader supercharger from aVolkswagen CorradoG60

The supercharger housing holds what is called thedisplacer plate(or justdisplacer), on both sides of which arespirals,withsealsbetween the latter and the housing. The housing itself also has spirals on both sides that mesh with those on the displacer. Driven by thecrankshaft,which is connected to thedisplacer shaftby a small belt, the displacer moves eccentrically with respect to the supercharger housing (like the rotor in aWankel engine) and, through this motion, forces the intake air into a smaller and smaller space, ultimately producing a maximumgauge pressureof 0.8bars(11.6psi) with standard delivered pulleys.

Sizes and car models

The German nameG-Ladercomes from the shape of the supercharger (German:Lader), which looks like the letterG.The displacer's spirals are either 40 millimetres (1.57 in) deep or, in the larger version, 59.5 millimetres (2.34 in) deep, i.e. close to 60 mm. This is the reason we see the engine designationsG40andG60in the names of Volkswagen models in which it was used:

• Volkswagen Polo Mk2GT G40(Typ86c - 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 Mk2FGT G40(Typ86c)
• Volkswagen Golf Mk2 GTI G60(Typ19E)
• Volkswagen Golf Mk2 G60 Rallye(Typ19E - limited to 5000 vehicles)
• Volkswagen Golf Mk2 G60 Limited(Typ19E - limited to a special Volkswagen-Motorsport series of 71 vehicles)
• Volkswagen Corrado G60(Corrado -Typ53I)
• Volkswagen Passat (B3) G60 Syncro(Passat -Typ35I)

See also

• G60- for detailed information on the complete G-Laderengines,and subsequentVolkswagen Groupforced inductiondevelopments

References

• "G-Lader Arbeitsweise (G-Lader Function)"(in German). Die G-Laderseite.de. 1998–2009.Retrieved2008-02-09.
• "G-Lader.info (Volkswagen G-Lader)"(in German). G-Lader.info.Retrieved2009-07-01.
• "G-Lader TIPS und TRICKS!".BAR-TEK®.Retrieved2024-04-16.