Okay, I did some analysis on this dyno run based on everything I know about the conditions and then going over the graph to see what it might tell me. I'm going to break it down a little bit so that those who are unfamiliar with what the graph can really tell you can see this.
If you look at just the torque curve you can see that there is hardly any benefit from a turbo this size below 2500rpm. At that point the curve starts off much like a normal 3L engine, but by 2500rpm is starts a slow climb. Then as boost starts to build the slope gets much more positive.
By comparing with a pressure gauge you can see when you start getting a positive benefit from the turbo.
With five runs to compare and one at 3.3psi, I can see that this turbo/engine reaches 3.3-3.5psi at about 2500rpm. This is pretty good considering I don't really need more torque below this point due to traction and launch issues, but I like a little boost when cruising to increase efficiency and No-downshift type passing. By 3000 rpm the turbo is taking over and by 3500rpm (~64mph) it's all over....the car starts to become a rocket and you get a huge increase in power.
Boost continues to climb rapidly. It looks like the boost spike up to 12psi is happening about 4400rpm(~77mph).
You can see that by looking at the first peak, the first area where the torque maxes out. Then the torque curve takes a downward dip as the boost level leaks back down to the 10psi range....that is the flatish section in the middle that has a decreasing slope due to the boost controller problem, and shouldn't be happening.
Basically with a turbo, as long as you are in the efficiency range, you will get an almost perfectly flat torque curve since the wastegate is regulating boost to an almost constant pressure. The tip off that there was a problem is that this curve never flattened out, even for a little while(normally 500-1000rpm range) and it started its downward trend immediately after the torque peak.
Finally, the second point on the torque curve where the slope of the line becomes even more negative, the more downward flat section corresponds to the fuel enrichment that is taking place.
Demon has mentioned that this last part is probably the catalyst overheat protection kicking in. I have not disabled this feature in my software yet and it allows the PCM to add fuel to bring down combustion temps in order to keep the catalyst from overheating and cracking.
IF the boost controller worked and the cat protection was disabled, we estimate a more linear torque curve with a much more gradual drop down around 6700-7000 rpm.
This would mean torque levels staying above 300 ft-lbs till probably 6500 rpm and maybe 290 ft-lbs by around 6900rpm.
With just these basic fixes, we estimate that it probably will pull 380 wHP at a constant 12psi with cat protection turned off.....with no real increase in risk to the motor since the torque peak of 334 ft-lbs is still down lower in the rpm range.
