If you adjust the wastegate rod, your ecu will detect the change and immediately adjust (retard) performance to compensate. After startup, you'll have a second or two of increased rush, but after that any performance gains are self-delusion. The ecu controls turbo operation to defend against premature burnout of the turbo, and to provide longer engine and drivetrain life. It's a good system.

If you want more power, you can upgrade the ECU program (expensive, but will provide more power AND turbo protection), or you can bypass the ecu with a manual boost controller but your turbo will be more at risk because it WILL run hotter. (Dial up the boost controller too much, and you risk damage to the engine,too: there have been some posts about bent piston rods with this kind of device.)

The way in which the ecu defends the turbo is by restricting boost under certain conditions. For example, on extended highway runs my turbo runs with less continual boost as the ecu slows down the turbo and switches more toward normal aspiration. When accelerating from 0, boost comes on incrementally as speed rises (and intertial resistance decreases) resulting in less drivetrain wear and cooler turbo operation. The ecu permits wide-open boost only for a few seconds at a time (you may never reach this limit as you'll probably be over 100mph when the clock runs out), again keeping the turbo from gaining too much heat. My indy tech is seeing 850 t-5s and R's with 300K on them, and has yet to repair a turbocharger.

David
(98 S70 T5SE Black, misc mods (mostly lighting), red calipers) (92 940GLE)
(Previous: 86 240DL / 88 745T / 94 945T)