a friend of mine has a 1.4 R5 turbo running 24psi of boost and putting 300BHP to the tarmac. he used to be a pit crew machanic and knows how to build a motor but it still blows every 3,000 miles. I dont see how a puny 1.4 will handle a turbo and supercharger, However the Wolfburg boys did turn smokey diesels into power houses so im sure they can manage this!
Thing is, the R5 engine is a manky old 2 valve per cylinder pushrod item that is based on 70's French technology (ie none). Even in standard trim, the renault 5 GT Turbo was fragile (take it from me, I killed mine). No matter what you did to these things, monster power meant monster boost, which meant they would eventually blow themselves apart.
The engine that Volkswagen are using is considerably more complex/technologically advanced and will be built to withstand the boost involved. Additioanlly, the idea is that the supercharger provides the boost at low revs (as it is chain driven in winds up with zero load required) and it is then replaced with the turbocharger as the laod (and therefore exhaust gasses) get the turbo spinning nicely. It's not going to be a mega-boost monster!
