Q: “A little debate going on regarding a rule on when to accelerate. I’m of the belief that you accelerate when at the apex and you can start to unwind the wheel. Am I being too simplistic? I’ve studied a number of pro driver’s videos and they all seem to be consistent in acceleration when they start to unwind.”
A: Your guideline (not a rule, because there are exceptions!) of starting to accelerate when you begin to unwind the steering is good. You can also turn that around and say that you unwind the steering when you begin to accelerate. The reason for this, of course, is because of what we know from the Traction Circle or “100% Tire Rule” – you can only get 100% of traction out of a tire (see the YouTube video I did at https://youtu.be/QgVmMv9bmkI). If you want to use some tire traction for acceleration, you have to unwind the steering and give up some cornering traction.
But where you begin accelerating or unwinding the steering wheel and how that relates to the apex is not consistent enough to even make a guideline out of it. The acceleration/unwind point may be before the apex, at the apex, or after the apex. It depends on the radius and length of the corner, as well as banking/camber and surface grip. Oh, and how your car handles. And your speed. And… well, lots of things!
In some cars you need to wait for a fraction of a second to let the car finish rotating so it’s pointing out of the corner before you begin applying the throttle. This could be before, at, or after the apex. And in some cases (relatively rare), you begin unwinding the wheel before you begin accelerating. The reason for this is that you need to let the car rotate further around the corner so that when you go back to throttle, you’re able to commit all the way and go to full throttle sooner.
The fun challenge of driving fast on race tracks is there are no real rules! There are guidelines, and I think we’ve outlined at least one here – but there are always exceptions.