I have run NGK platinums in my DSM and without fail the car will start to miss past 18psi (1.2 bar). And yes I realize stock is platinum but I think that's more of a service issue for Audi than anything else seeing how much of a pita it is to get at the plugs.

2001.5AudiS4 Sold, waiting for an Elise
2005 Jetta TDI Wagon
Vag-Com Heaven :)
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