Originally Posted by 4sevens.com
With every tire there is an optimum slip angle with produces maximum grip. Before and after this "peak" grip falls off. With slicks that peak is really sharp with the greater angle falling off really fast. What I'm describing is loading both outside front and rears right at the peak - that is the fastest you'll ever go in a corner. Loading both is not so much the "perfectly netural setup" but rather how you drive the car. With any car anywhere near close to neutral a skillful driver can load front and rears evening - trust me, I've worked up to this point. I take student's cars to this limit all the time. (there are lots of little advanced tips I can tell you but thats beyond the scope of this thread)
It is at this point, where you are at peak grip (optimum slip angle) that the car is basically at it "limit." The limit of the fastest you'll go around a corner. It is at this limit that tiny tiny changes in power will cause your car to exit the corner less than optimal (over/under steer) requiring correction. And if you're on slicks the tiniest big of power change can throw you into a wild goose chase after your wheel.
hehe I like describing these experiences
bottom line. I don't shift mid-corner if I'm driving race pace. If I can actually shift mid corner (even though the shift is very very fast) then I'm leaving more on the table and need to go faster through the corner lol
Agreed on the fact that there is a portion of the turn where both, the front and the rears, are very close to that optimal grip point. But they won't be for the entire turn. During turn-in the fronts are working more and as you power out the rears are working more (on a RWD).
I also agree on the fact that I would avoid shifting during that critical phase where both axles are at the maximum grip point, which usually is around the apex. Further, it is rarely the point where you would require an upshift...
Usually, if an upshift is required, it be will during track out; and at this point the shift becomes quite manageable.
Further, there are some turns that are simply taken flat out (no braking at entry) so there is no real way to take them any faster (unless you add a SC
). These turns are not taken at the optimal grip level, so to your point, no issue with shifting there.
So you could be at race pace and shift while in a turn (albeit not anywhere in the turn
The original point raised in the thread related to the concern that the power shift (the surge) experienced with DCT in the more aggressive modes would cause the tires to abruptly lose traction if they are under lateral load. I think we can conclude that DCT was programmed smartly enough to allow shifting during a turn quite safely and much more easily than with a MT. But it remains with driver to do it smartly