Q: “When and in what type of car can you upshift in a corner? In certain slower corners I’m exiting with an RPM that is low in the torque curve, but a lower gear would be past the redline before I get the car straight. What do I do to make the best exit out of this corner?”
A: I’d say that it’s very rare that upshifting in a corner is ideal. If I – or a driver that I’m coaching – have to upshift before the end or track-out point in a corner, I take that as a sign that I need to make the next higher gear work.
As you point out, if you’re in too low a gear you’ll get to redline before you get to the straight after the corner, and then you’re having to upshift while the car is unbalanced. So, what’s wrong with upshifting in a corner? Well, just that – the car will be unbalanced, meaning the load/weight is transferred to the outside tires, and off the inside ones. When the car is like this, it has less grip than when it’s balanced, and combined with having the steering wheel turned, it’s possible to upset the car so much that it leads to a loss of control. Oh, and in some cars, it’s just awkward having to shift and steer at the same time.
So, your goal should be to upshift just as you get to the track-out point of a corner, or shortly after that. Sure, every now and then, you’ll find a corner where you might have to upshift just barely before the exit, but again, that’s rare.
As I said, if I have to upshift before getting to the exit of a corner, I use that as a sign that I need to drive the corner in the next taller gear. Yes, at first it might feel as though the engine is bogging, and it’s probably not going to sound as good. In fact, the lack of the engine revs often triggers the thought that you’re not going fast, but that’s not always the case. I’ve coached drivers to use a taller gear in a corner – let’s say, third gear instead of second – leading them to come in and tell me that they were slower. But when we look at the data and sector times, the driver is shocked to learn that they were faster using the higher gear. Even though it doesn’t sound or feel as fast, sometimes it is.
Plus – and this is the most important part – take the use of the taller gear as a challenge. If it feels and sounds like the engine isn’t revving high enough, then work at carrying more speed through the corner. That might mean braking slightly lighter approaching the corner, or releasing the brakes a little earlier so you don’t slow down quite as much. Even one or two MPH can make the difference. Make the taller gear work for you.
Of all the things I’ve coached drivers on, using a higher gear in some corners is amongst the things that have had the biggest impact of lap time improvement.
Also, a couple of related answers are here:
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