has no one suggested a boost leak test? I know Im just a little dsm'er talking here, but normally when we experience fuel cut it is due to the fact that there is a leak in the lower or upper intercooler pipe, the intercooler itself, the intake manifold (yours truely...lol), the throttle body, or the bov. any leaks anywhere after the turbocharger at high boost levels become HUGE problems and lead to fuel cut. what you need to do is pressurize the system, look for leaks, and then spray where you think the leak is with soapy water and see if it bubbles. if it does, theres a whole in the line. really common leaks for us are the throttle body shaft seals, but thats probably due to age. how you pressurize the system is you take off the intake pipe, use a silcon coupler to attach a pvc cap of the right size to the end, and install a bike valve in the pvc cap (before you clamp it down that is), then use compressed air in the system to look for a leak. pressurize it to 20+ psi (don't overdo it or you'll just blow off the pipes) and look+listen. We normally do 20psi for 30 seconds mininum, but with cars that are from the factory at 20 psi, I dunno how high you guys should go. Obviously if it can hold 60 psi forever your in great shape, but dont try 60 psi and expect everything to be fine. try like 25 psi or 30 MAX.
remeber, this is just a dsm'er who has watched the top gear where they test the evo VIII vs. a lambo like 5000 times. Those power slides were enough to sell me on the fact that my next car will be, without a doubt, an evo 8, 9, or hopefully (active braking here I come) an evo X. now I just need that green stuff, I think its called money? I dunno, test driving these things at my local dealer will have to suffice until I have the money for an X.