Originally Posted by CanAutM3
I guess it all depends on how a specific car is setup and balanced.
As you reduce the propulsive force due to the higher gear, some of the rear leteral grip is lost due to the shift in weight towards the front. However, since less of the rear tire grip is used for longitudinal acceleration, more lateral grip becomes available (think friction circle).
For a given setup when upshifting, I guess it could be possible that the lost grip at the rear due to the weight transfer outweighs the gained grip from the friction circle. In this instance it could probably lead to a spin...
However, it is not the case in my car. I do feel the change in yaw, but no instability.
True - but also depends on how you're loading your outside front and rears. If you're truly at your limit on both front and rear, maximizing your grip mid corner, any power change will cause bad problems. If not, then you're probably not at your grip limit - in fact thats how I usually detect how well I'm loading both fronts and rears... if theres more room to wiggle the wheel or play with the throttle then I'm not at the limit. The absolute limit mid corner it a beautiful and delicate thing