~4K rpm cutout... help!?
 

All I have is a DP and MP for mods, I've done the turbo system simplification per Rob Robinette's site and put on the complete Fischer Racing (spyfish007) block off plates. Now, what I tried to hit boost or go to WOT... the car cuts out like it's hitting the boost cut. I need to find out what's causing this...

Do you have a boost gauge? If you do, you'll notice that the boost have dramatically jump past 10lbs. The stock ECU is only design to provide fuel up to 10lbs; over that the fuel will cut off. You'll need a fuel cut-defendser. HKS and Greddy makes it for the FDs. Don't forget, you may want to invest with a stand alone ECU, upgrade the ECU, or purchase a piggyback computer to compensate for the higher boost. Good Luck!

Yeah I am planning on getting a fuel cut defenser, but the best thing you can do know with those symptoms your experiencing, which was what I was experiencing is to run Octane 94 gasoline, it worked for me, and it works really good when the car is filled right to the top

I run at least 93 octane all the time. I was going to try and put the stock cat back on to see if that cures it. It's old and needs to be replaced w/ a high-flow or something. I hope it's just the fuel-cut...