"Power brake", what's that? Have you tried holding up the power brake (emergency brake) switch instead of pushing the floor brake? You mention a c. 200 RPM deficit doing the "power brake". And you hold the accelerator for darn close to the maximum allowed before LC disengages. That seems dicey to me (but again, I know nothing and less than nothing about drag racing!). I have to do this again to answer some questions about RPMs falling off when you hold your right foot down; not a lot, but I am pretty certain that I did detect a dropping of several notes when I pushed down, held it and then released the brake: prompting me to abandon the LC and just hold the car in place with auto hold, and then floor it swiftly. It seemed that I got away faster that way (entirely a gut judgment, and we know how subjective the gut is, heh ).