Perhaps a poll should be taken. Some tuners seem to have more conservative numbers than others. What is the real hp of our zo6. 405-50, -60, or -70. These numbers are floated around quite a bit. I don't know whether or not a tuner is incappable of producing good numbers or is just giving a conservative estimate. I know of two vendors who seem to have different views on drivetrain loss (50 vs 70). What do you think.
Percentage can produce erroneous results. M12 drivetrain loss in HP at stock engine redline is known to be 50HP. If you change cam and you make max power at 6800 rather than 6200, you add 10% friction, so you now have 55HP loss.
The stock LS1 makes max HP at 5600, so the loss was only 45 HP.