WOT switch gives only 49.5 duty cycle

[DGraber460 at aol.com]

Now that I've tweaked the wastegate spring, I'm finally ready to purge the 
last few small gremlins from the URQ.
I've wired my duty cycle meter to the interior so I can monitor it under all 
conditions. I have found that under full throttle, the ECU gives it a rock 
steady 49.5%. Spec is 77%. I have the idle set at a mid 40's range, and the 
O2 sensor is new.
All the other sensor readings and other settings are to spec, and the 
switches (both idle and WOT) work as specified.
The result is that full throttle isn't all it should be.
This isn't a result of the wastegate mod, but has always been this way. I'm 
wondering if the ECU hasn't been previously modded, as a boost level of one 
needle width below 2 bar doesn't activate the fuel pump cutout. 
Any ideas?

Dennis
PS This car is starting to give fruit of labor for all the blood sweat & tears