VW Corrado G60
The initial concept of the Corrado was derived from the Mk2 Scirocco and was to be badged as such (Mk3 Scirocco) but in 1984 it was decided the Mk2 Scirocco would continue, and it did so for three years after the Corrado as we know it was first manufactured.
Volkswagen Corrado G60 Karmann History
Manufacture of the Corrado G60 began at the Karmann Factory and Volkswagen was aiming to rival the likes of the Porsche 944, so from the off, the build quality that Karmann Coachworks offered was a good start. The main opening body panels were Zinc plated, and the shell was partly Galvanised. This along with being heavily wax oiled (A patented process), means that the Corrado G60 is still with us today.
The 0-60 time of the Corrado G60 was a sore point for many, the reason being that an extra gear change is required as the gearing does not allow for 60mph in second gear. The 0-60 time would have been much more respectable otherwise. One of the features of the Corrado is the active rear spoiler which raises at 45mph and lowers at 15mph automatically, it can also be operated via a button on the dashboard. Volkswagen claim that the spoiler adds down force for increased stability at speed.
The G-Lader Supercharger (Lader German for loader) was patented by a French Engineer called Léon Creux, 3rd October 1905. Originally it was developed as a rotary steam engine pump but the design required extremely high manufacturing accuracy which could not be reliably achieved at the time, so the project was halted.
Two fixed spiral chamber housing halves compress air between a shaft driven eccentric Magnesium displacer, giving a ‘G’ shape and hence G-Supercharger or G-Lader. Self lubricating apex strips are used in contact with the displacer which create a seal, helping to produce an efficient compression of air. The G60 Supercharger used on the Corrado (PG Code Engine) has a displacer depth of just under 60mm, hence ‘G60’. A timing belt is used on the crank driven displacer to ensure that there is correct clearance.
The G60 Supercharger was never given a maintenance schedule by VW, but there are internal bearings (Including oil fed from the cylinder head) which do wear with time. Most G-Laders have been rebuilt at some stage with new bearings, seals and apex strips as they have been known to explode, especially with the use of smaller pulley’s.
Now the VW Corrado G60 we had in the workshop had previously booked in for a rolling road session as the owner felt that it wasn’t running very to good and could smell fuel inside the car. The car was strapped down to the rolling road and was run. Immediately we could see that the car was not fuelling correctly and that the exhaust was blowing badly. The car was booked in for a few weeks whilst we investigated the fuelling issue and ordered a shiny new Jetex exhaust system.
The Jetex exhaust arrived and the car was put on the ramp for the fitting. Unfortunately the previous owner had made some modifications to the exhaust system and a new catalytic converter had to be ordered and fitted. This made a huge difference to the awful smell of petrol in the car. So now it was time to crack on with investigating the poor running. Unlike newer cars we are not able to plug the diagnostic machine into the Corrado to get a more accurate answer to why the fuelling is out so we had to go back to basics and start double checking everything. Some of the sensors had been replaced but with the car being 24 years old parts aren’t always just sat on the shelf and where second hand so these needed to be tested too! After many hours of checking over wire connections, timing and sensors we hit the jackpot and the car ran like it did back in the 90’s.