RenesisEvo
Whoever said that changing up gear in a bend is a problem - why?? I do it all the time - no extra oversteer, no slower out the corner. And if it changes down - big deal?? Or just try holding R2? Manual is only good for when the CPU refuses to change down or lets the car bounce of the limiter for ages before shifting up. Any other time - not worth the hassle. I'd rather be looking where I'm going, not at the speedo/tacho; or straining my ears for that certain note that suggests I should change up.
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That would be me!
Changing gear in a bend at speed will seriously upset the balance of your car. If your tyres are already at their maximum slip angle then any sudden change in car balance or speed (such as a gear change) may well exceed the slip angle. The tyre will lose grip and you will lose control.
As has already been said, if this is not happening, then you are not going as fast as the car can.
Personally I drive in GT as I would drive at the track, in the following order.
1. Start braking before the corner
2. Downshift as braking towards the corner, ensuring the gear changes are finished before the corner
3. Start to ease off the brakes as I enter the corner (trail braking)
4. Constant throttle throughout the corner; maybe a small lift or touch of left foot braking to keep the racing line
5. Accelerate out of the corner; gently feeding the power on as the front wheels straighten
6. Full throttle with the wheels straight and start shifting up as you head to the next corner
For me this is by far and away the fastest way round a corner, and by getting all the work down before the corner its quite easy.
Anyone who find this difficult should start wil a fairly slow car and just practice, building up speed and the power of the car you use.