04-12-2006, 10:38 PM
Put it this way... the amount of braking force you can put into a tire varies dependent on the vertical tire loading (ie weight) until the tire reaches its maximum terminal braking force. That's a gross simplification, but it works.
What does that mean? Say you're driving a car with 50/50 weight distribution at constant speed. So you have no weight transfer, ie static weight distribution is what we work with. Let's say our car weighs 1000 pounds, so you have 500 pounds on the front tires. Welp, you plant the brakes, you've only got 500 pounds pressing down on the tire (normal force) and that's also the only thing that keeps the tire from locking. So the tire locks pretty easily.
If we brake lightly and put 60% (600 pounds) of our weight on the front tires, we can brake harder because we have more normal force to resist lockup due to braking force. 70% (700 pounds) on the front tires, we can put in more braking force up until the point we reach maximum tire loading (hypothetical 80% here). So you now have a mathematical relationship between weight distribution and braking force. If you plot braking force against tire loading, you'll see it makes a nice smooth curve. If you want to ride the edge of that curve and brake as hard as you can throughout the braking zone, you will need to brake just like the curve... smooth. Increase braking force as you increase front tire loading. Spiking the brake pedal takes you above the curve, and makes the tire lockup. Instead, ramp your pedal force up smoothly and it will work better.
Efficient brakers brake quickly, but ramp their brake pedal force. If you plotted brake pedal force against time, you'd see there's a nice smooth curve there as well, assuming there's not some reason they're trying to upset the car.
BTW, the first time you come off the brake rapidly after totally using the brakes into a turn... you probably won't want to do it again for a little while. Heh
What does that mean? Say you're driving a car with 50/50 weight distribution at constant speed. So you have no weight transfer, ie static weight distribution is what we work with. Let's say our car weighs 1000 pounds, so you have 500 pounds on the front tires. Welp, you plant the brakes, you've only got 500 pounds pressing down on the tire (normal force) and that's also the only thing that keeps the tire from locking. So the tire locks pretty easily.
If we brake lightly and put 60% (600 pounds) of our weight on the front tires, we can brake harder because we have more normal force to resist lockup due to braking force. 70% (700 pounds) on the front tires, we can put in more braking force up until the point we reach maximum tire loading (hypothetical 80% here). So you now have a mathematical relationship between weight distribution and braking force. If you plot braking force against tire loading, you'll see it makes a nice smooth curve. If you want to ride the edge of that curve and brake as hard as you can throughout the braking zone, you will need to brake just like the curve... smooth. Increase braking force as you increase front tire loading. Spiking the brake pedal takes you above the curve, and makes the tire lockup. Instead, ramp your pedal force up smoothly and it will work better.
Efficient brakers brake quickly, but ramp their brake pedal force. If you plotted brake pedal force against time, you'd see there's a nice smooth curve there as well, assuming there's not some reason they're trying to upset the car.
BTW, the first time you come off the brake rapidly after totally using the brakes into a turn... you probably won't want to do it again for a little while. Heh
Chris Perera
Team Shocker
90 Integra r3d/bl00
91 Civic Si gr33n
02 WRX bl00
Team Shocker
90 Integra r3d/bl00
91 Civic Si gr33n
02 WRX bl00