2023 Season Started- Intuitive Line Optimization

At Our Local Site Milton Frank Stadium (Photo Ashley Eyles)

In Lincoln at Nats last year I was asked by a well-known autocross blogger & teacher why I hadn’t been publishing much lately. I told him I only write when I think I have something new and interesting to say. This was the truth… it’s always been the case. And there will be a new idea contained in this post, as always, but I’ll get to that in a moment. In the meantime, there’s something else.

The Plan

Even before Nats last year I’d determined to make a big push to improve my driving, both the mental and physical aspects. When it comes to line theory I figure I know enough. When it comes to car setup for Street class, I figure I know enough. Silver Ghost is handing better than ever now that I have RE71RS tires on the front and A052s on the rear and revalved shocks that eliminate the 20% too stiff mistake I made the first go-around. Plus, I verified that the Corvette is quite the different animal with Yokohama A052 tires on it. I no longer think that it’s fully competitive in BS without the increased ability to put down power that the Yokohama tires confer.

My plan for this year has been to attend as many local/regional events as I can manage with specific objectives in mind. As I put it in the Nationals wrap-up post last year: …you must make the most of each run you do get to really develop a disciplined, decisive and consistent driving style that eliminates big mistakes entirely. I plan to make the most of a lot of runs this year.

Things have gone well so far. I’ve done seven autocross days in 2023 for a total of 57 runs. However, my plan to go to the Red Hills tour, the first national event of the season, was stymied. I started feeling poorly just before the event and just after confirmed exposure to a bad case of Covid. I cancelled at the last minute. Turns out I just had a cold and would have been fine at the event.

To make up for the loss of Red Hills I plan to add the Peru tour this year, not previously in the plan, followed only two weeks later by the double event at Bristol. As for going back to Nationals this year, I’m on the fence. Last year’s event left a decidedly bad taste in my mouth. I’ll let my rate of progress and the tire situation weigh heavily on the decision to spend the time and money. Going to Nats last year without Yokohamas on the rear of the C6 was a colossal mistake, but not for the reason I assumed it might be before-hand. Turns out it was the Yokohama compound’s aversion to picking up OPR that made the most difference, not the ability to put down power, which is the advantage at Tours and locals. Neither course last year needed power. I probably never used more than 200hp and 70% torque. The courses were just sweeper after sweeper, not transient-heavy (which would have favored the Falkens) and no digs. All that mattered was grip and grip depends mostly upon weight to tire ratio and the tire compound. I tried my best to get the Yoks last year based on the strong recommendations of others, but it didn’t happen. The lightest, least powerful car in the class won and can do it again if the courses this year are similar.

Breakthrough

I had a type of mental breakthrough at an event a few weeks ago. I achieved a mental state during the third run in the morning that I’ve been intentionally aiming toward for some time. I found myself dispassionately watching this ‘other’ person driving. I was able to watch myself scanning ahead, feeling everything coming through the points of contact between myself and the car, feeling every bit of grip or lack thereof, watching my mind racing to analyze the line at each point on the course, how far off I was from my planned line at each location, whether I was on the gas early enough, observing the rate of brake application and the rate of torque application, whether or not and how close I hit each planned apex, and observing and modulating that key balance between aggressiveness and smoothness that is so important for driving fast and at the limit without hitting cones.

Driving Solo

Something different this year from the last couple of years is that I’m driving alone. The initial thought was for the low heat tolerance of the Yokohama tires. I’ve heard many complain about how they could not get the tires cool enough between runs with two drivers in really hot weather. Driving alone makes that problem much easier to handle, if not eliminating it altogether. Spray once right after each run and you’re done, even on a hot day.

Yokohama A052 Tires- Worth Their Weight In Gold And Almost That Expensive

Another key reason for driving alone is to give myself more time between runs to analyze data. I’ve never done much between-run analysis before, always spending lots of time after each event analyzing data, but not so much during the event. (At Nats last year on Thursday and Friday the entire time in between runs was spent cutting OPR off the tires. And that was with at least two other helpers, sometimes three, including my co-driver.) This past weekend I was able to intentionally drive sections of the course differently in the first two runs and then look at the data, decide which approach was faster and successfully alter what I did the next run.

A third reason for driving alone is the sorry state of affairs of SCCA grid work at tours. It seems that the ability or desire to determine a proper split point within run groups has been lost. At no Tour event I attended last year was an attempt made to split the run group to equalize the time gaps between 1st and 2nd drivers. As a result, two different days we got the you’re-the-5th-car notification within 30 seconds of the previous driver pulling into the grid spot. I was made to feel like I was interfering with the event when I complained, requested to be put onto a 5 minute clock and then sometimes refused to leave when told to go until we had our tires watered and the pressures set. To top it all off, twice after receiving the quick 5-car warning and rushing to get the car ready, the grid master then totally forgot about me and never came to my row. The first time I had no clue what had happened. I just proceeded on to the start when I felt like it. I have no idea if I was in the correct order. The second time it was clear that there was a systemic issue so I got out of the car, tracked the grid master down and let him know I’m going back to my car and will proceed to the start line unless he has some objection. (How the 5-car person knows where I am and that I’m in a two-driver car but the grid master doesn’t I never understood. He apologized later… to my co-driver.)

I’m also doing more post-event analysis than ever before by exchanging data files with other people and working up an analysis for each one. For the event this past weekend I got files from four different drivers. It requires many hours but it’s necessary, just as in any other sporting endeavor, to achieve a high level of performance.

Thought Experiment

Speaking of achieving a high level of performance, let’s do a little thought experiment. I’m going to list the capabilities I think one must acquire to reach a high-level in autocross driving, not counting things like car preparation, testing to determine tire pressures and temperatures, etc.

Here’s the list:

-You must be able to walk a course, accurately imagine how it will drive, make a clear plan for how to drive it, and then drive it on the limit on the first try. You must be fast on the first run because the course is not the same if you drive it much under the limit and you only get three tries which means only two chances to figure out what to do differently. This requires a lot of experience and various forms of deliberate practice. With regard to experience: After 100 events do you have 100 events of experience or do you have 1 event of experience 100 times?

-After each run you must be able to remember what you did well, what surprised you that you need to now consider and what was not done so well. You must then develop a clear idea of what you’ll do differently and why in the next run to get faster. Without this you cannot drive smarter, instead of just harder. When I first started autocross I had almost no ability to remember what happened within the last run, what was good and what was bad. I would completely forget about huge screw-ups that I did notice one minute earlier during the run. Sometimes the memory of them would come back an hour later. Very strange. Over time the mind gets better at this sort of thing, but you have to be focused and insist that it happen by getting into the habit of mentally reviewing every run immediately upon its finish.

-You must be up on the latest understanding of what constitutes the most efficient lines for standard corners, chicanes, curved acceleration zones, increasing and decreasing radii corners, one, two and 3-cone turnarounds, the effect of sloping surfaces on the line, etc.

-You must have the tactile sensitivity to feel and then understand what is happening at the tire patches and recognize how the grip is constantly changing from run to run and from moment to moment within a run, along with complete mastery of manipulating weight shift forward and back to optimize turning rate and braking and acceleration performance.

-You must have the car control skills to drive the car at the limit of tire adhesion while maintaining a precise, as-planned driving line that has the tires just barely missing or just barely kissing the key cones without resulting in a penalty. It goes without saying that you can’t slide too much or spin, either.

Do you think that’s a pretty comprehensive list?

It’s not. I left one big elephant off the scale that, I think, is the key difference between good and great autocross drivers and out-weighs many of the necessary-but-not-sufficient points above.

Intuitive Line Optimization

There are just too many variables. Autocross is nothing if not an exercise in multivariable optimization, and no two events are ever the same.

Heck, no two runs ten minutes apart are ever the same.

We don’t get to practice the course like in circuit road-racing and the course layouts are often much more complicated, even unacceptably weird, compared to fixed circuits. (If it was up to the road-racers the course designer would often get locked in a trunk and then they’d go out and “fix” the course.)

There are no course guides on the internet to study beforehand because no one has ever seen the course before. (Well, excepting that one year at Nats…) There isn’t much in the way of standards to guide the course designers, though there probably should be a few more than there are. How clean is the surface? What’s material is it? What type of aggregate is in what type of concrete or what type of asphalt? (Barber Proving Grounds is mostly high-grip asphalt but has one section of even higher-grip concrete. Next week I’ll be there pointing out to the Novices that at one location it changes from one to the other in the middle of a corner and they need to take advantage!) If it’s asphalt has it been sealed? Sealed everywhere or just part of it? How thick is the sealant? Is it the same thickness everywhere or have certain areas been worn down? (Less sealant usually means more grip.) When did it last rain? Is the surface bone dry, a few water molecules per square centimeter, a little damp, full wet, standing water, deep puddles? Will it be the same when you run? Is gravel getting produced on the racing line as the day goes on? Is the surface abrasive and causing the tires to shed rubber that collects into “marbles” and gradually dictates a tighter line as the day goes on, even if it’s not right for your car? Which corners get camber in what direction in this particular course design? Which parts are in the sun, which are shaded? What’s the temperature? What time of day is your class running? Where are the bumps, what kind of bumps are they and how bad are they? How many cars are on race rubber that deteriorates faster than street tires and thus produces more marbles? Where are your tires on the continuum from new to nearly worthless?

There’s not enough computing power in the world to analyze it all even if you had exact data on every variable. This means it’s a perfect job for the human brain.

The best drivers look at and think about all these things and more while they walk the course. If possible they watch other cars run, especially cars and drivers they know are fast. They intuitively alter their plan of attack from the theoretical to match the actual and optimize for the shortest time through the course. They take one run and optimize again. They take another run and optimize a last time. They drive the third and last run on that course and then it’s done and dusted, gone forever.