lghjr,
We are on our first trip with the ScanGauge, up the Oregon coast into Washington. The transmission fluid temp is not working, it displays 2450 to 2500 while cruising and goes to 2750 with moderate load. There are four XGauge data sets for the 2010 Ford CANSF protocol, only one of the four shows any info. I am currently working with Scangauge support to figure out what is going on.
Since reading your post, I watched the horsepower gauge, I was always able to get the max 300+ hp if the rpm was at least 4000. If you are at a speed under load that does not allow the trans to downshift to get the rpm up to the 4000 range then you won't see the max hp even with the gas pedal to the floor.
Torque for the V10 is fairly level from 2000 to 3500 rpm with max at about 3200, hp increases steeply with rpm with max at about 4200 rpm. There is an XGauge for torque, you may want to watch that instead of hp to see if your V10 is producing the max torque at lower rpms. Torque is a direct measure of force (ft-lbs) whereas hp is a measure of work and is calculated from measured torque and rpm: hp = (torque (ft-lbs) x rpm) / 5252.
That is an over simplified description, but you may see that you need high rpm to see max hp, but max torque is available at a range of rpms. Try Google searching for hp and torque curves for the 2-valve V10, interesting info.
Bob