Help with argument... real HP and estimated HP

Well with that time (assuming the mph is equivalent to the time)...he needs that car to be tuned...or he needs to learn how to drive...he spent to much money for all that...IMO...

Need the whole time info to guestimate hp. It may be as simple as a tuneup that will net him the power. I went from 12.5x @ 110 to 11.6x @ 116 with some race tuning.

Still too much $$$ for HP

Well, estimations are just that. Using track data to calculate Hp/ft-lb is inherently flawed to the infinite amount of variables that go into the end result. It is not accurate data.

The only way to accurately measure horsepower & torque of an engine is on an engine dyno and the only way to accurately measure horsepower & torque of the combo at the wheels is on a load-bearing/eddy current dyno (Mustang). Inertial-type dynos (Dynojet) will get you close, not accurate measurements. There was an interesting MM&FF article about this a few years ago where they took vehicles and did a few hits on each of the two dynos. One, there seemed to be a bit more variability in the measurements achieved by the inertial-type dyno, whereas the Mustang dyno's numbers were very repeatable...and two, the numbers were always lower when the hits were done on the Mustang dyno. Part of the reason why is that in the real world engine load increases in a non-linear fashion due to wind & rolling resistance, drag coeficient, gearing, etc. The Mustang dyno's computer has software built into the system to mimic this type of load environment and because of this, more accurate load data can be used for drivability tuning and/or maximizing power.

Did I just go on a tangent? Sorry.

Bottom line. There is no sense in arguing. Get it on a dyno and measure it. End of discussion.