Corvette Z06 GT3 Part 2

Corvette Z06 GT3 Part 2

Choosing Brake Bias, Anti Lock Brakes and T/C

Front Brakes Locked

Brake Bias refers to the % of total braking power directed to the front. The higher the Brake Bias the more likely the front wheels will lock up under braking--obviously this is a bad thing because once the front tires are locked up the driver can no longer steer the car. The lower the Brake Bias the more likely the rear tires will lock up--this is bad as generally the car will immediately spin.

On cars with Anti Lock Braking, turn off the ALB or more correctly the ABS and attempt to execute "Threshold Braking" from 100 mph. Adjust the Brake Bias lower if the front tires lock up-higher if the rears lock up. You can see what's happening by looking at the RF/RR or LF/LR replay views. When you have lowered Brake Bias to a point that the rear tires lock up and handling is unstable, on the Corvette with 5-7 gallons of fuel load, you will be at close to 51.8. Raise the setting to 53.8 to insure you NEVER lock up the rear brakes. 

Front and Rear Brakes Locked at 51.8

In addition, set the ARB and T/C to 2 to allow the computer to help you drive. Very skilled and experienced drivers can run with ARB and T/C at 1. Less skilled and experienced drivers may find the ARB and T/C setting at 3 to be easier to drive.

Another reason for the higher Brake Bias is that even though the rear tires are not locking up, applying brakes in the corner in order to Trail Brake will reduce the sideways grip of the rear tires and the car will have more oversteer.  Increasing Brake Bias will reduce corner entry oversteer but the price that is paid is lower total braking power--you will have to brake earlier with higher Brake Bias. You can brake later with lower Brake Bias as you are utilizing more total braking power--utilizing more of the potential braking from the rear. 

Keep in mind that GT cars have less relative downforce and more weight transfer. Brakes need to be applied earlier than formula cars and weight transfer can make the car feel loose under heavy braking-a fact you should have noticed in the testing described above.

Drive the car and experiment with small changes to see what best suits you. This setting can be changed from the cockpit during the race. Highly advanced drivers will change this setting for different corners during the race!

Traction Control is also adjustable from the cockpit. As mentioned above, it is allowing the computer in the car to help you control two things--wheel spin and yaw. Yaw is the rotation of the car when changing direction. T/C comes with a price--if you exceed a certain predetermined set of conditions (too much wheel spin or yaw) the computer takes almost complete control of the car away from the driver. Much more difficult for driver to "save" with high T/C setting. You have surrendered some of your control as a driver to the computer. (And the guy or gal who wrote the T/C computer software).  It should also be noted that T/C functions by applying brakes and reducing throttle—so T/C will almost always slow you down.

Be aware that the optimum Brake Bias depends to a great extent on how much brake force is being applied.  The Corvette is a heavy 3000 pound car with a higher center of gravity than a formula car--weight is transferred from the rear to the front during braking. The harder you brake the more weight is transferred. The weight distribution on the Corvette is 40% Front/ 60% rear. Under heavy braking this may change to 55% front and 45% rear, so Brake Bias settings depend to a degree on how heavy you tend to push on the brakes. 

The Corvette allows you to choose the type of brake pads. It has been said that the low friction pads allow more “modulation” but this is a myth-you will just have to push harder on the pedal. Muscle memory is most accurate at medium levels of leg/ankle/foot force.

In addition, the Corvette has a large displacement engine, so downshifting is like applying the rear brakes only. If you are an early downshifter, you may want a higher Brake Bias to avoid spins.

Cockpit Adjustments