The TME people have tried it, and **they** know the ECU program inside-out (since they write the programs that go on the IPD chip upgrades). And they'll tell you it's complete waste of time. The ECU detects the change and compensates within a second or two. Fun's over.

If you really want to beat the system (as well as the turbo, and to a degree that's up to you, your engine) get a manual boost controller. Dawes makes one. And it's cheap. Bypasses the CPU entirely and let's you dial up all the boost you want...enough to bend your throw rods if you want. (It's happened, as has been reported on this board.)

Or change the ECU program with the IPD/TME chip or some other. Short of the bypass device, this is the only other way to control the wastegate (as well as fuel-air parameters).

Keep in mind the ECU does a couple things. First, it protects the turbo from prolonged operation at extreme temperatures - this is the number one reason why the turbos in 850's and later models hardly ever fail. My 88 745T (with the exact same water cooled turbo) needed to be rebuilt twice because it lacked the ECU safeguard...that model had an oem manual boost controller. Second, the ECU protects your engine. Modern metallurgy can only do so much to hold off the laws of physics; excessive heat and pressure will shorten engine life, period.
--
David \\ (98 S70 T5SE Black, misc mods (mostly lighting), red calipers) (92 940GLE)