New answers tagged turbocharger
Turns out the previous owner of the car adjusted the wastegate actuator in an attempt to increase boost pressure. The sudden loss of boost came about because the ECU forced the wastegate open in an attempt to keep the manifold attached to the engine ;) Kudos to whomever wrote the software for the Bosch Motronics unit.
Both engines you mentioned have a supercharger and turbo combination. The performance difference is achieved by increasing the boost pressure to the engine. While this might be done only by using different ECU maps for small performance differences, the big performance differences usually require higher capacity parts as well, especially for the turbos, ...
The differing specs of VW engines are (I believe) mainly done by varying the ECU maps - Which is why a lot of power can be gained from the lower-spec engines by chipping them up to (and beyond) the higher-spec versions.
Top 50 recent answers are included