the motor will do fine. building the head & adding cams will help though. the turbo will go b4 the motor does. i run 25 psi on 101 octane unleaded. (see my sig on the '03) i will soon be adding Tomei 280 cams, a PWR air/water i/c, & maybe a HKS Kansai intake manifold. then i will spike the turbo to 30PSI also & let it taper. the problem is that everybody is quick to take off the stock turbo but no one really maximizes it's potential. the stock turbo maxes at around 500 crank hp believe it or not, & i still have gained some topend (Thanks AL!!) sitting at 20 degrees of timing on stock cams & stock ecu.

 

i run 22 to 23 daily on godawful himid ga weather and ct9 runs 28psi daily on the same weather with the alky kit.

run 23 psi, you'll get a boost cut at 24psi on stock 03 turbo with non reflashed ecu.