Braking - Turn Fast! The Road Racers Reference Center

Discussion in 'Autocross/Road Racing' started by Bud, Jun 27, 2008.

  1. Bud

    Bud GG EVO IX MR

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    Ohhhh Dave.....you fellas are nuking it! I understood it BEFORE I read your stuff....now I'm confused. I guess this is one of those things you need a lot of seat time to understand....I dunno!
     
  2. Quick

    Quick Mgmt. - I can't help you

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    No, I think I understand what they're trying to say. They just suck at explaining it. It's also kind of inexcusable to mix or incorrectly use well defined terms. Might be easier for the layman to understand what they are trying to say but then the reader will be under a misconception that's going to confuse them later.

    What they're trying to say is that for maximum performance you need to be turning the steering wheel further than your intended line. If you're taking the corner at 80 mph you need to turn the wheel more than if you're taking the corner at 5 mph. That IS due to slip angle. That is NOT due to slippage. They totally mucked up the explanation of why. To the novice it may FEEL like it's slipping/skiddng but it's not. End result is that their audience now thinks that maximum traction is achieved with some amount of skidding. Not true. If you're not flexing the tire (slip angle) you could be more aggressive. If you're skidding (slippage) you've gong too far.

    You agree with that?
     
    Last edited: Jul 6, 2008
  3. DrBob

    DrBob New Member

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    Slip angle

    Yes! I agree with the idea of slip angle as opposed to slippage. In practice, approaching the engineered slip angle of the tire generates the most traction. Exceeding that slip angle results in less traction but not necessarily lost traction. Really exceeding the angle can result in loss of control (tire squeel) until speed is reduced enough for tire to regain traction. It is all relative.

    The faster you go on a race track or even a fast freeway onramp the sooner you have to put steering input into the car because as speed increases, steering response, the result of tire traction, slows down. Turn the steering wheel at 40 miles per hour and the car responds immediately or seems to. Turn the wheel at 100 mph and the car takes longer to respond so turn in must be done sooner. I think this is because the faster you go, the longer it takes the tires to approach their ideal slip angle, generate its maximum traction, and communicate that "feeling" back to the driver who is supposed to be in control.

    I am sure a tire engineer can explain it much better, but I hope this explanation doesn't "suck" too much


     
  4. HalV48

    HalV48 They Call Me Patron

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    Go Speed Racer, Go Speed Racer, Go Speed Racer Now!
     
  5. Bud

    Bud GG EVO IX MR

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    Bump
     
  6. dms

    dms LX Suspension Specialist

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    to protect the tires and allow them to work to their max will require the suspension system to be totally compliant. The LX suspension has a lot of excess looseness. fix this, adjust the cambers and front caster to assist the tires going in/out of a turn, and your lap times will be faster and safer. What you may find, however, is that you will be able to enter/exit corners better and faster, but you will end up requiring better brakes to match the increased speeds that you will be at

    mike
    dms