The manual says Race Start will rev engine to 4k rpms, then let off the brake. I've watched videos and the tach hits 4k on the dot, smooth and even, in those vids.

In my 2012, the revs get to 3,500 then gets rough, though it stays in that general area. I've made sure I have good quality high octane non-ethanol gas, but it still does this. Yes, I am putting the accelerator pedal all the way down, pushing the little button under it.

If the car is in park, the engine will rev smoothly all the way to redline.

The car is going in for 60k mile service soon and I will put this on the list of things to check. I'm suspecting a knock sensor is retarding the revs. Any other ideas of why this odd behavior? I hope it's something that can be fixed because I don't really feel like this car is giving me 500+ hp.