Came across a couple of articles on the VR30DDTT turbos in the SS & RS.....The Stillen article below is especially interesting given their expectation that the maximum safe psi level that can be run through the turbine compressor is about 17psi
Here's what they state:The VR30DDTT is an impressive motor. It is underrated from the factory as we have seen with dyno testing. The Hi-Output version is rated at 400 hp and 350 ft-lbs at the crank and the Low-Output version is rated at 300 hp and 300 ft-lbs at the crank. We have consistently seen ~375 whp and ~350 wtq from the Red Sport Q50’s and Q60’s and ~300 whp and ~290 wtq from the “300 hp” versions.
That being said, everyone is still excited to see what these motors can do. With factory forced induction there is often a ton of room for gains when you simply tune the car and crank the boost up. Now there is a lot to consider before assuming power gains by simply increasing boost and tuning. So strap on your thinking caps and prepare for the math!
The factory turbos on the VR30 are produced by Honeywell-Garrett. The model of the turbo is MGT14446LKSZ. We could talk technical specifications*, but in the end let us just say the turbos are small. What is more important is we have the turbo map for the MGT1446 turbo. This has allowed us to see what efficiency range the turbos are operating under stock boost, as well as the limits of the turbos when it comes to boost levels and power gains.
Closing statement:"So aside from changing the turbos (which there are no upgrades available at this time), what can we do to safely increase power? We believe it is unwise to spin these turbos much past 17 psi in search of a lot more power (at least above 5000 RPM)."
Although we probably won’t be seeing any 600 whp Q50’s or Q60’s without bigger turbos, there is still a lot of potential even on the factory units. Needless to say, we are all working on more ways to make power with this platform. STILLEN is about to release our new intake system for the 3.0t Q50 & Q60 along with our Cat-Back Exhaust for the 3.0t Q50! Our engineering department has done a lot of work on these products and designed them with the factory setup in mind as well as future upgrades.