Sam Low's Library - Speed

Lime Rock - the Uphill

The Masters' Class

Excellence Magazine

February 1999

 

By Sam Low

 

 

The track at Lime Rock, in the bucolic northwestern state of Connecticut , meanders gracefully around the base of a hill. Spectators sit on the hill beneath tall oak and maple trees, as if attending an open-air concert. Zen-like in its simple beauty, it's a fitting place for a master's class on the intricacies of merging the human mind with mechanical sinew.

 

On September 25, 1997 , about 80 Porsche Club drivers assemble in Lime Rock's Paddock. By invitation only, two dozen of these drivers will be paired with a guru of speed, Hurley Haywood or Price Cobb, for a half-hour tutorial in the cockpit. The rest of the day will be for testing.

 

Henk Westerduin of Porsche Club's Hudson Valley Region thought up the concept: "It's a time to check your skills against the real masters of the art, to really get beneath the skin of your car, to try a setup, run it on the track for a few laps, come in to check tire temps, dial in another setup and run again."

 

For the Porsche Club, such a test day is an innovation. For professional racers, it's an essential step in tuning their machines to suit a driver's individual skills. IndyCar teams, for example, spend weeks testing their machines during the preseason on a number of road courses, ovals, and super speedways. The test day's success depends on a driver's mental prowess.

 

"A good test driver has the ability to go out and drive consistently lap after lap so that he can feel the changes we've made to the car, and he can relate those subtle changes to each type of corner and come in and tell me in an understandable way how that affected why he went faster or slower," Ray Leto, Bobby Rahal's engineer, once told me. "Whether it was a good change or a bad change, Bobby can run a determined number of laps in the same way and tell you what's going on. It's so important."

 

Successful testing also depends on a close relationship between driver and engineer, as Rahal explains: "My communication with my engineers and their ability to decipher what I'm saying and come up with solutions is the key to going fast."

 

7:30 am : In the thin air of early morning, ice crystals sheen the windshields of race cars in the paddock. Some are brutal, their graceful shapes are blunted with wings and cages. Bulges around bloated tires mar a once svelte flow of line. Others are stock, almost feminine in the presence of their highly-modified brethren. In comparison, my 914-4 seems tiny and ancient. It's as if a biplane suddenly appeared in a squadron of Saber jets.

 

In the company of elite PCA club racers and track instructors, I wonder how I will stack up. Last year was my first year of racing, and the presence of carburetors in my engine compartment kicked me up to class "I," where I was uncompetitive. This year, with a new fuel-injected engine, I am doing well in "J." But today I am sharing the track with drivers like Ron Savenor and Mark Forrester, Tom Bobbit and Henk Westerduin, the best of the club's racers and instructors. Accompanying me is my engineer, Dick Shine of Shine Racing in Walpole , Massachusetts . Dick has been building race cars for 30 years. He rebuilt my 914 by stiffening the cage, adding needle bearings of his own design to the suspension, and tweaking it else-where. Dick knows what he is doing, but do I? Will I remember how the car felt on each corner? Will I be able to communicate that feeling to him? And what will happen when I share the cockpit with Price Cobb?

 

8:30 am : Drivers' meeting. Price and Hurley stand at casual parade rest, backs to the timing stands. They shuffle from one foot to another, regarding their students.

I first met Price Cobb five years before in a car setup class he taught in Dayton , Ohio . He was the ace, the pro. But he spoke across the divide that separates amateur racers from professionals without the slightest hint of its existence. He will be my instructor.

 

10:00 am : Price straps into the passenger seat. "Don't scare me," he warns. I laugh. "No, I mean it! I want to see smoothness, repetition, consistency. When you drive a race car, it's always like taking someone on a date. You treat them with infinite respect and kindness. Remember, on a first date you're always walking on eggshells, you are never sure. Well, with a car you should always be never sure. If you take the car by the scruff of the neck and you're trying to force it around, then you can no longer react when the pink elephant jumps out in front of you. If the car is at the limits, there is nothing left. I tell everybody, the only time I want to see the car at the limits is at the apex."

We go out. After two laps without comment, Cobb says, "you drive well. The only thing I can suggest is that you ask yourself why you lift off the gas sometimes. Is it a comfort factor?"

 

"Yep, sure is..." I don't elaborate. Some of the turns still scare me more than they should.

 

In the left-hander, Price comments. "The car seems a little twitchy."

 

10:10 am : We pit and change over so Price can drive. In the left-hander, he says, "The car oversteers by itself. It seems to have a rear axle with a mind of its own. I'm going into the pits."

 

We come into the pits. "It's not you," he tells me. "It seems like the rear is toeing out as you turn the wheel. I was doing nothing and the car was wanting to rotate on me. There's something worn out or the alignment is not right. I tell you right now, you fix that and you will be real quick."

I turn the car over to Dick Shine. He dives under it, checking the suspension. Meanwhile, Price and I sit on the pit wall. I ask him about Lime Rock, the rhythm of race tracks, and how when a car is just right it feels like you are skiing.

 

"Right. But to use the metaphor, you have to ski each track a little differently," he expands. "Most road circuits like Lime Rock are like a giant slalom. Most street circuits are like doing moguls. It's almost brutal. Very on and off. Speed in the corners is almost non-existent, so what's left? Well, braking to the Nth degree and accelerating to the Nth degree. It's a different kind of rhythm, much more harsh. A place like this is very flowing. In fact, at a place like this, you want to spend more time coasting than braking. The car will slow down as soon as you start turning the wheel. When you realize that, you learn that the car will also slow down in a more controlled manner. So remember that thought. Roll off the throttle a little earlier. Many people tend to brake heavily into a corner which upsets the car a lot, loads the nose, and unloads the rear, which makes it awful tail happy. Be gentle, find the rhythm."

 

On the surface it's a familiar lesson. Be aware of how braking and accelerating loads the car how it places dynamic weight on the front and rear. But beneath it, there's a deeper thought. A driver must partner with his car, feel it, treat it as a living thing. Open a conversation with your machine, Price is telling me. It's a refrain that will be repeated all day,

 

Noon : The sun renders warmth. Cars circulate. In the paddock, Ron Savenor and Mark Forrester are changing tires. I find Dick at the pad aligning my car.

 

"Hats off to Cobb," he remarks.

 

"Why?"

 

"Your right rear trailing arm was loose. It must have been wobbling around a lot."

 

One lap, I think. Just one lap and he not only found the problem, but identified the exact source. I go out, circulate for a few laps and come in. "How did it feel?" Dick asks.

 

I look blankly at him. I thought we were doing tire temperatures.

 

"I mean, was it pushing? Was it loose? Where?"

 

No one has asked these questions of me before. I have asked them of myself, but now I can't remember the answers. So this is a test day...

 

"Take a break," says Dick. He takes the car back to the paddock. Down pit lane, Hurley and Price are huddling with Mark Forrester, Ron Savenor, and Henk Westerduin. Like fighter pilots, their hands weave imaginary chandelles in the sound-shattered air. Haywood is talking: "All my students tell me 'you turn in earlier and brake much later than I do.' In general they are of the school of late apexing into a corner. "Their lines are theoretical lines, but our lines are racing lines. A racing driver always thinks how to go through that corner the fastest way but also how to eliminate someone from overtaking on the inside. So our entry into the corners is always much earlier. We take an early apex, so we are carrying much more speed from the mid-point to the exit point of the corner. It's an unnatural line because you're not used to it, but when you do get used to it, you will say, 'Oh that feels much better' because it's much less of a struggle with the car."

 

Makes sense. In driving school, we are taught to brake hard and turn in latebecause it's safe you have more margin for error. If you make an early apexyou can run out of room on the exit.

 

"A corner is a mathematical equation," Hurley continues. "Point A the entry Point B the exit. And you want to have the path of least resistance between those two points. Most people want to turn the car too much going into a corner because that's what they feel safe doing. They bind the car up in the corner, and that upsets the balance. When you upset the balance, the car is screwed up. You want to loosen the car up."

 

I edge closer to the informal classroom. Cobb begins to talk.

 

"Think of a glass with water in it. If you are cornering at 100 percent, the glass is full, you are using all the grip."

 

Cobb's hand slides toward an imaginary apex.

 

"Now, if you want to accelerate you can't because the glass is already full. People tend to overbrake and then bring the car into the apex and hold it there as they apply power, pinching the car. I think of trading lateral grip for linear grip, cornering for acceleration."

 

A glass with water in it. Cobb's illustration is a nice metaphor for the most basic principle of traction management. If you use all of the traction in your tires' four contact patches to brake, you have none left for cornering. If you use all of it for cornering, there is none left for acceleration. If you hit the apex of the turn using all of your traction for cornering lateral grip there will be nothing left for acceleration linear grip. So go in slower, come out faster.

 

"A car's lap time will come from its ability to accelerate and use its power,so I say trade some cornering capacity for some acceleration capacity" Cobb continues. "Trade some braking for some cornering. You have to know where to make the trade and when. It's like the stock market. But do it gradually so you can feel if the trade you made is being accepted or not. You are cutting a deal with the Devil. When you are out at the limit, you have to figure out how to trade acceleration for braking."

 

"I tried it and it worked," says Ron Savenor. "It reduced understeer and I was really able to step on the gas and carry more speed from the apex on. From braking to the apex was slower, but from the apex to the exit appeared to be smoother and faster."

 

Early afternoon: Dick has the car ready to go out.

 

"What did you do?" I ask.

 

"You tell me," he responds.

 

A lap to warm up the tires. Into the brake markers at the end of the main straight just before Big Bend five, four, three lift, squeeze on the brakes and turn in. Does the car feel a little less positive? It seems to drift further from the apex than before. Did I make a mistake? In the uphill and West Bend , it happens again. I come in. Dick waves me into the pits.

 

"It was a little further away from the apex, almost everywhere," I tell him.

 

"So it's pushing?" he coaxes.

 

"Yeah. Pushing."

 A lesson. Dick had tightened the front sway bar. Next he loosens it to show me oversteer. During a normal driver education day with a series of 20-minute sessions, there is no time to make adjustments and then go right out and try them. Now, running back-to-back sessions with adjustments in between, I am learning what to look for. To feel the changes. A test day needs a test driver, as Ray Leto told me. So I have to remember exactly what went on in each turn and communicate it to Dick. Gradually, I begin to shed the amnesia that grips me when I come into the pits. The trick to that is using both sides of the brain what I call the "Price Cobb Zen Lesson." Cobb told me to file the geography of the track into the subconscious side of the brain and let the subconscious keep track of the braking, turn-in, apex, and track-out points. Then let the conscious part pay attention to what the car is doing and file those lessons away.

 

"When you have to constantly think about applying the brake, turning the car, accelerating then you will be slow," Cobb told me. "When it is all ballistic, from prior training and images and memory, your body is absolutely quicker. Try to keep your subconscious out of it once it has been programmed. That will allow you to concentrate on what the car is doing." When I can do that, I feel like I am flowing in unison with the track. Then, and only then, I can listen to the car. It's a conversation that raises questions.

 

"The driver and the engineer must always ask themselves why," Cobb told me. "'Why do I lift? Why do I brake exactly there and not there? Why brake at all?' There are endless things to think about! But that's what testing is all about. If you come to a track and go around and the lap times are never changing, then you are not learning anything. And I mean that from the bottom of my heart. You haven't increased your knowledge. Even if you go backwards in lap times that's increasing your knowledge because you know you don't want to do it next time."

 

Dick and I go back to our testing. We drop the tire pressures. Raise them. A formula emerges, 26-29-29-27 are the cold tire pressures around the car, clockwise from left front which come up to 35 psi all around when the tires are warm. It makes sense, of course, to have lower pressures on the left because the turns at Lime Rock are mostly to the right. The left-hand side ofthe car is working harder and the tires heat up more. To tame the push, Dick tries raising the rear spring rates. We go from 200-pound springs to 275, transferring

some work from the overloaded front tires to the rears. The car settles down,and is neutral in the corners. Lap times dip into the mid sixes. But still, there is the problem of the left hander. The trick is to stay high, turn in relatively late, allow the car to rotate, then accelerate and take the next righthander flat out as you enter No Name straight. But when I try that line the car pushes badly, it won't turn in. I relay all that to Dick.

 

"Where are you braking?" he asks.

 

"About fifty feet before turn-in."

 

"Brake later. Try braking just before turning. Try left-foot braking."

 

I go out. I know what Dick is trying to do. Braking will settle the nose, make the front tires bite. I try it. Too early. Another lap. Still too early. Then, just right feather throttle, tap and turn. On the next lap, all wrong. Brake too late - or something. Trees whirl around the cockpit, the hill appears, the track... Locked up, I raise dust and excite yellow flags.

 

"Well, it's something to work on," Dick suggests.

 

Slanting sun. Golden hour. The clock winds toward shut down, but cars still circulate. I walk around, asking students what they have learned. Henk Westerduin gained more feel for his car: "Feeling exactly what it's doing at precise points on the track," he explains. "The car might be neutral coming into the corner and start to understeer coming out under power. Paying more attention to every point through the corner."

 

Ron Savenor and Gary Archembault learned to turn in earlier and brake less: "Before, I used threshold braking," Gary tells me. "Cobb has totally gotten away from that. He says, 'there is no rule that you have to goflat foot down the whole straight. Let off a little earlier and let your momentum carry you into

the corner. Feel the car stabilize and then just touch the brake a little and the car will be much more settled going in."

 

Mark Forrester learned critical lessons about tire management. He came to the class with a problem; half-way through a race, his tires would go away. Haywood gave him the solution.

 

"I'm coming into Big Bend too hot, and when I turn in I can feel the left front tire which is just scrubbing along and that is the source of my fronts going away. Where I'm killing my rears is in the left-hander. I'm throwing the car into it and that right rear is getting hammered there." Haywood showed Mark a different line turn in earlier and let the car float out instead of forcing it into the turn and overheating the tires. "In the left hander, you end up much wider than you think you want to be. What he did then was just lift big time and the car would rotate and he was back on the gas."

 

When I asked Steve Bower what he learned, he showed me his hands big open calluses. "Here's a clear symptom of my problem," he said. Haywood hammered home the 'first date' rule: don't force the car, feel all the signals from the steering wheel. "Hurley was just holding the wheel with the tips of his fingers," Steve said. "I have a tendency to hang onto the wheel and move it around a lot."

 

The lessons span a spectrum from the mundane details of spring rates and tie rods to a sublime insight into he workings of the human mind. But there is a common thread all good drivers must learn to carry on a conversation with their machine. Like all good conversations, it requires a knowledge of your car's capabilities and its idiosyncrasies. It demands patience and sensitivity The ability to listen.

 

It may sound easy, but at speed when both sides of my brain are carrying on a frantic shouting match aimed at, well, survival it's a conversation that I find a trifle difficult. But it's precisely this conversation this debate between the left and right brain - that makes driving at high speed so exciting and intriguing.

 


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