Hmmm... I just did the following : - I disconnected the output pipe (bottom) of my Forge DV007P from the hose. - Sealed that (air-intake/MAF) hose with a cork and a clip So now my 007 is actually operating in fully atmospheric mode. NO fault codes or engine lights yet ?!? (I have the AUQ engine btw.) (don't even care, because I have VAG-Com to reset them if needed). And it gives a truly awesome woosh-sound !! (More a 'POOOOOF') Car performs normally. It's easy to change te setup once in a while, by simply reconnecting the 007 to the hose. Or I could even make a T-piece with a tap in it (!), to change between atmospheric and recirc "mode" ... So guess I won't even need my Split-R. (anyone interested ??) Today I am going to route a hose from the 007 output to the grille, and experiment a little with some different sized caps at it's output, to get the nicest sound ) So it DOES appear to BE possible to have a fully atmospheric blow off valve on a 20VT ... Anyway , What's the worst that could happen ? Some fault codes, or maybe a slightly little lower petrol mileage ?