Maximum Street Speed Explained, Part III

Jack Baruth
by Jack Baruth

It was just another day at the “Tail Of The Dragon” for the group of experienced sportbikers clustering around the Robbinsville, NC, gas station. Fresh from multiple high-speed runs down the famed road, they were reliving their victories when a long-haired old man in some girly convertible asked them to “show him the fast way through.”

“Fuck off. We don’t wait for old cagers,” was the reply. As fate would have it, they didn’t have to. Five of the six knee-draggers had to yield to that old man in his Porsche-with-panties before the halfway point. The sixth and fastest made a mistake, went off, and snapped his fairing into three pieces. The nice old man stopped and helped him carry his bodywork to the “Tree of Shame” at the Dragon’s end.

Contrary to what you read in Car and Driver, we can’t drive “10/10ths” on back roads. In Speed Secrets, Ross Bentley talks about the bell curve of tire traction. The more we ask from the tires, the more we get . . . but as we reach the limit of traction, the rate of slip increases. As we pass the “peak” of traction, the tires “fall off” at the same rate . . . but now we have no safety margin for gravel, road waves, animals, and whatnot.

We need to stay on the safer side of the tire-traction curve. That means we drive up to the audible squeal but not past it. To make this happen, we drive what I call the “Safe Line.” This is what I teach to novice racing students, and it’s the only “racing line” we can use on back roads.

Approach each turn at the very outside edge of the pavement. For right-handers, this means either the edge of the double-yellow or the far edge of the road, depending on your vision and personal risk tolerance. Brake in a solid, single swift motion, “squeezing on” and “easing off.” If you over-slow the car, that’s fine. Wait longer next time. But don’t re-accelerate this time. When you have completed braking, turn your head past the “clipping point” of the turn, which is either the inside curb or the double-yellow, focus on the exit, and make a single turn-in motion. Keep constant throttle until you reach the clipping point, then unwind the steering wheel before applying throttle for the exit.

Since we are not on a racetrack, we don’t trail-brake, we don’t “adjust” the car in mid-corner with left-foot braking or throttle inputs, and we don’t even think about applying power until the car is pointed properly to the exit. Most importantly, we take the absolute latest apex, which is to say that we wait as long as possible to turn the car into the corner before turning sharply. This reduces mid-corner speed, but it also reduces inadvertent corner exits.

To do this quickly, you need “traction sensing”: the ability to guesstimate potential corner speed the first time you see a turn. I can’t give that to you. You’ll have to earn it over time by steadily increasing the speed at which you approach known corners until something goes wrong.

Racetrack time doesn’t help much here. Racetracks don’t have pavement waves, big bumps, salt, gravel, dead animals, or Amish people in horse-drawn carriages. If you see any of those, you’re either on the road, or you’re at Nelson Ledges Road Course for a “Friday Funday.” Forget what you know about on-track traction sensing. You can be an SCCA champion and still finish your first Ohio backroads drive in close proximity to a guardrail or tree. Ask me how I know.

Between corners, we accelerate at full speed until it’s time to brake for the next. The exception to this is when we run “The Pace.” The concept of “The Pace” is an old sportbike maxim: set a maximum speed between corners and treat it as a hard ceiling. On the backroads group drives in which I occasionally run, that ceiling is 110mph. Go faster than that, even for a moment, and you can go home alone. No exceptions.

If you enter a corner too hot, straighten the wheel and apply full ABS. Chances are you will go off, but you will go off slow. If you find yourself “saving” a turn by braking in the middle, guess what? You had enough traction to make it through on the throttle.

When you are in mid-air from a “whoop,” do not hit the brakes. Relax your hands and make sure your thumbs are clear of the steering, and keep the throttle at the same place you had when you left the ground. Oh, yeah: keep your eyes up for other road users and treat ’em with courtesy, of course. Pass with care.

Part IV is the finale, in which we discuss suburban and urban techniques.

[Click here to read Part I or Part II of this series. Note: as these editorials have triggered some strong emotions, I’ve turned off our no-flaming the website/author policy. Ish. I reserve the right to douse particularly egregious examples, in an entirely first amendment friendly sort of way.]

Jack Baruth
Jack Baruth

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  • Stein X Leikanger Stein X Leikanger on May 24, 2009

    @DearS Did you find that your "traction sensing" improved? I did, just by reading. Yes, Baruth said he can't give it to me, but he did. I'm all apexed out.

  • Gzuckier Gzuckier on May 24, 2009

    this article is all good advice. if you don't like the concept of people taking this advice at 100 mph, then think about them taking it on a wet icy highway at 50.

  • The Oracle Well, we’re 3-4 years in with the Telluride and right around the time the long term durability issues start to really take hold. This is sad.
  • CoastieLenn No idea why, but nothing about a 4Runner excites me post-2004. To me, they're peak "try-hard", even above the Wrangler and Gladiator.
  • AZFelix A well earned anniversary.Can they also attend to the Mach-E?
  • Jalop1991 The intermediate shaft and right front driveshaft may not be fully engaged due to suspected improper assembly by the supplier. Over time, partial engagement can cause damage to the intermediate shaft splines. Damaged shaft splines may result in unintended vehicle movement while in Park if the parking brake is not engagedGee, my Chrysler van automatically engages the parking brake when we put it in Park. Do you mean to tell me that the idjits at Kia, and the idjit buyers, couldn't figure out wanting this in THEIR MOST EXPENSIVE VEHICLE????
  • Dukeisduke I've been waiting to see if they were going to do something special for the 60th Anniversary. I was four years old when the Mustang was introduced. I can remember that one of our neighbors bought a '65 coupe (they were all titled as '65 models, even the '64-1/2 cars), and it's the first one I can remember seeing. In the '90s I knew an older gentleman that owned a '64-1/2 model coupe with the 260 V8.
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