Slalom vs. Slalom

I’ve always assumed that there are parallels to be found between downhill ski competition and autocross. I never bothered to look into it, until now.

Full disclosure: I never became anything more than an intermediate recreational skier. So, you ski-racers out there can comment and tell me where I’ve got it all wrong.

Four main types of ski-racing events seem to exist at the world-championship level. The event called Giant Slalom (GS) most closely parallels autocross, I think. It runs about 1 second between gates, basically the same as an autocross slalom. The distance between gates varies a bit and sometimes there are two gates to pass on one side, but there are ranges for proper course design based on vertical drop. From Wikipedia, based on a formula: “… a course with a vertical drop of 300m would have 33 to 45 direction changes for an adult race.”

Maybe we could learn something about standardized course design for national autocross events from ski-racing.

The second type of event, Slalom, is shorter in length than GS with faster transitions and only about .82 seconds (I saw this number somewhere) between gates. I think this was the first type of ski-racing of the four to be established. Slalom transitions are faster than most, but not all, cars can achieve.

Of the two so-called speed events, Super Giant Slalom (Super-G) I’d say is most similar to Solo Trials and the Downhill is more comparable to road racing. The speed events have gates set farther apart, thus allowing higher velocities, are longer, have big radius turns and not much in the way of quick transitions.

From my brief reconnaissance of the sport, ski-racing technique has evolved rapidly over the last 20 years and maybe much longer. Much of this change has been driven by the evolution of equipment, in particular the advent of scalloped (side-cut) skis. As equipment got better humans have had to adapt their technique to take full advantage.

The ski-racing authorities have imposed limits on the equipment to keep things from getting out of hand, to keep things (somewhat) safe. They’ve had to impose minimum ski length and side-cut radii for each of the four types, for instance. They’ve had to change these requirements more than once. We call those “take-backs” in autocross, of course.

Something vaguely similar to equipment limits is happening in autocross. As power-to-weight ratios go up along with lateral-g’s in the lower prep classes, the courses at most venues have to necessarily get tighter to keep the maximum speeds in the safe range.

In general,  however, I’m not sure we can say that autocross evolution has been much driven by equipment evolution. While street tires have increased rapidly in performance, and street cars certainly handle better straight off the showroom floor than ever before, there have always been race tires and race cars at a much higher level of performance. That’s where most evolution due to technology has occurred. Someone with more knowledge than me will have to discuss whether better race tires have caused evolution in the classes where pure race tires are used.

Not that I think autocross is static. Far from it. I think it has been evolving fairly rapidly over the last 15 years or so. I think the best drivers of today are faster than those of 25 years ago. The reason? One word: data.

It’s almost comical what some people considered gospel 25 years ago. Data has cleared away a lot of the rubbish, the old wives tales, and the many ideas borrowed from the more mature sport of road-racing that just don’t apply to autocross. I think data is still driving autocross (and, for that matter, road racing) evolution today.

So, most of the talk/forums/instruction in ski-racing deals with human technique, and rightly so, especially since there are significant physical dangers in the sport, but there is some thinking about line and course strategy.

For instance, “high and early” vs. “low and late” discussions about apexing gates are common, especially with respect to the best line for beginner vs intermediate vs expert. Most teachers seem to recommend completing about 2/3rds of the turn prior to the gate, except for an expert skier who may do more of the turn after the gate. I’m sure the reader will recognize the direct parallel to autocross. I’ve done quite a bit of related data analysis elsewhere in this blog. Turning high and early is equivalent to late apexing in most peoples’ minds (not mine… I think that phrase should be banned from autocross as it is almost invariably misused) or, more properly, “back-siding the cones.”

I was particularly struck by the thoughts of Bob Harwood in an essay entitled The Road Not Taken- A philosophical approach to line and tactics, published on-line at

Mr. Harwood writes “…what Bode [Miller] has taught us is that the old myth of one right line, the high line, is simply not true. Bode has learned that if he rocks his weight back a bit at the apex of his turn, he can ski a lower, tighter turn and still carve. Bode is able to bend the tail of the ski with more arc to carve a small radius turn with a high degree of confidence. Bode also has an amazing ability to shift his weight forward at the end of a turn so he can initiate the next turn smoothly and not get caught on the back of his skis at the start of the next turn. The end result: Bode’s balance and skills let him ski a lower, straighter line with less chance of DNF-ing than a more tradition skier…”

Sound eerily familiar? Race car driving has often been boiled down to the aphorism “The driver is simply a manager of shifting weight.”

Example: I recently co-drove a BS S2000 at the last two regionals of the year. I’d never autocrossed an S2000 before. The first event I wasn’t particularly fast. I focused on an efficient line and not spinning. (I spun anyway. But only once.)

Several places I took too slow of a line and dropped out of VTEC, which you really don’t want to do in an S2000 if you can help it. By the end of the day I had managed to get a feel for how much I could slither the rear of the car and yet not spin. I managed to beat the owner by a small amount but we were both down in the standings… I PAXed 17th of 112 and 8th of 9 in Pro, down from my average position.

In between events I watched a particular video (here) over and over again. This video shows a split-screen comparison of the best runs of Geoff Walker and co-driver Matthew Braun in an STR S2000 at the 2014 Wilmington champ tour.

Geoff Walker is one of the guys from an adjoining region that I’ve always considered quite fast. I’ve been trying to match him for years. He trophied in STR at Nationals in 2013, one of the very toughest of classes.

Matthew Braun is simply one of the fastest autocrossers alive with multiple Solo National Championships and podium trophy positions. Lately he’s been 3rd in SSR in both 2015 and 2016, having been the SS National Champion in 2006, 2010 and 2012 and the A-Stock champion in 2003, just to name of few of his accomplishments. I’ve been lucky enough to meet him on occasion.

Walker was driving great, by my standards. As far as I can tell he only makes one slight mistake in the entire run, getting a little bit late in the first slalom. That’s it. Everything else is just perfect. Perfect, until you see what Braun does on the same course.

I see a consistent difference between the two. Braun takes a slightly smaller radius at each offset cone. He then rotates the car while going past and is able to get on the throttle earlier as a result of the car being pointed in the new direction sooner. He walks away from Walker with a higher average speed (and possibly a shorter distance traveled) at every point in the course.

Braun and Miller: Both take a tighter radius by controlling weight shift. Braun manipulates weight over, and lateral forces at, the rear tires and gets them to slide at just the right spot and rotate the car during a tighter radius turn. According to Harwood, Miller manipulates his body weight, bending the rear of his skis more, allowing him to carve tighter at the apex and take a more direct, and thus faster, downhill line. The parallelism between these techniques is striking to me.

Cause and effect are often difficult to sort out in autocross, but the 2nd event in the S2000 I beat the owner by a much larger margin, took 2nd of 6 in Pro and PAXed 6th out of 74. This is about normal for me, maybe even better than normal.


Zennish Autocrossing Survives!

Two things of note have happened since my last post. One, the Solo Nationals Appeals Committee upheld the decision by the Solo Nationals Protest Committee to reinstate the first 3 runs taken, wet or dry, in the weather-interrupted Heat 5 on the last day of Nationals. Two, Howard Duncan sent out an apology for letting the Steward’s appeal get in the way of awarding trophies to the people who deserved them. Well done and well said, Howard.

Zennish autocrossing survives!

Not only was it affirmed that the Steward did not have the power to invalidate legitimate  runs, it was affirmed that the Steward’s action, which she claimed to be enforcing the intent of the rules, was, in fact, contrary to the intent of the rules.

Did she actually believe otherwise? I doubt it. All indications are this is a woman with significant experience in both driving and officiating autocross. Many of her even more experienced fellow competitors told her she was wrong. She threw out the dry runs anyway. Then they officially disagreed with her by filing multiple protests. She could have stopped it all then, but she did not.

So, the Protest Committee heard the protests and told her she was wrong by upholding four of them and reinstating the runs taken before the delay. By appealing their ruling, she revealed the final act in a misguided attempt to single-handedly change autocross… to make autocross more fair. I’m confident she thinks it was for the good of the sport. What she really did was to attempt an end run around the rules-making process, an attempt which, if successful, might also save some face. Sort of like going to the Supreme Court in hopes of making new law via creative interpretation. Ain’t the way it’s supposed to work, that’s the legislature’s job, but in the words of the comic Judy Tenuta, “It could happen!”

Not taking multiple no’s for an answer, she attempted to get her fairness improvement encoded in an appeals committee ruling. Hoping they would say, “well, it was within her power as Steward and things surely were more fair in the end…” Thank God they didn’t!

Instead, the Appeals Committee said, “…it has long been the tradition and understanding in Solo that the weather “is what it is”…”

They went on to say, “We believe the lack of a rule addressing fairness and changes in weather [especially as the Solo Events Board has declined to enact any such rule when suggested in the past] reflects an intent that changes in weather not be the basis for discarding runs or declaring results “unfair.”

Now go howl at the moon, autocross zen-doggies.

Getting it done (in one)

While driving home from Ohio it occurred to me that fighting to not be dead last is exactly the same as fighting for the last trophy (as I found myself doing this weekend) is exactly the same as fighting for the class win. And it doesn’t matter whether it be at a regional, a championship tour or at Nationals. It’s all exactly the same.

More often than not the situation is this: you have one run left and it must save more time, sometimes a lot more time. Thou shalt not hit a cone, but thou shall be close. Thou shalt not slide or spin, but thou shall be at the limit. Thou shalt not make a mistake of any consequence.

So, we might as well figure out how to get it done in the one chance remaining while we’re still at the bottom of the time-sheet. Why wait?

One key is being able to remember and think back over the previous run to identify mistakes plus identify what changes will allow you to save more time. If you can’t remember the run vividly enough to identify mistakes, and if you can’t think of any way to at least possibly save more time, then you have little chance of achieving your goal.

Trying to drive harder usually won’t cut it. You’ve got to force yourself to think, man!

Like anything else, it takes practice. In this case, mental practice.


Falsely Accused of Driving Smoothly!

On a recent weekend I ran two different autocross events, one in Huntsville on Saturday and another in Chattanooga on Sunday. Both days, someone (not the same person) commented that I looked very smooth. How outrageous! Don’t they know that I once authored a blog post entitled Smooth Is Slow?

I guess the car looked smooth from their exterior vantage point. Both persons had been working on course during my run group. I can’t be certain, but I don’t think they were trying to slyly tell me I was slow. I was driving faster than ever. Too fast on Saturday, in fact, to stay off the cones.

Both courses were tight and busy. Inside the car I was working furiously, making a huge number of small, quick corrections at both steering wheel and throttle, moving the weight around, finding each scrap of grip available right at the edge of traction and on the precipice of loss of control. I was very busy and I felt nothing smooth about it! I guess since I didn’t spin, didn’t have any big slides and the tires were howling more or less at a consistent pitch and volume it seemed smooth to the observers.

I discussed this observer-versus-driver disconnect phenomenon in Smooth Is Slow. I re-read it just now. Still happy with what I said back then in one of my very first posts. This has made me ponder a slightly different subject, however, which has a connection to smoothness.

Most autocrossers have run into the following complaint about autocross from track-day junkies, usually when asked why they have no interest in autocross: Autocross is dumb because you spend all day to get 6 runs of 60 seconds each. Just not enough seat-time. On a track day I  get 5 sessions of 20 minutes each… that’s 100 minutes of seat-time versus 6 for autocross!

I’ve always thought there was something a little screwy with this position. If you don’t find autocross fun, OK. If you don’t care for the competition and can’t enjoy it while losing, well OK to that also. The seat-time argument, if intended to imply that you become a better driver faster, seems wrong to me.

I’ve found that many of the people who say things like this, despite many hours of time on the track dwarfing the time I’ve spent on the autocross course, are painfully slow when I get out there on track with them. (I’ve done  17 track-days. I like doing them. I’m sure I’ll do more.) Typically, they exhibit car control skills that I think of as mediocre at best, which causes them to drive what seems like a very slow pace in the corners, necessarily leaving a large margin for error. I’ve been thinking about why this might be the case, after all those hours they have on track, and have come to an idea about it.

The idea is this: it seems to me if you want to develop high-level car control skills there’s a fast way and a slow way. The fast way is most accurately measured by how much time you’ve spent at the limit of tire adhesion.

During a day of autocross you get, if properly aggressive, 6 minutes at the limit, more or less. It doesn’t matter what car you are in, how much horsepower you have, or what tires are mounted. Spending time at the limit is what counts when it comes to developing car control.

In that 100 minutes of track driving, the typical, sane person gets how much time at the limit? Zero.

None. Zilch. Not any a’tall, which is infinitely less time at the limit than an autocross gives.

Why is this? Very simple. To get to the limit you must go over the limit. Otherwise, you can’t tell, especially before you are an expert, that you got to the limit. Right? So, what happens if you go over the limit during an autocross? Worse case, you tank-slap spin and that run is toast. Guess what, though? You get to start up again, rejoin the course, and drive the rest of the run at the limit. You’re not out anything except a little tire rubber. Maybe you don’t win your class that day. Maybe you don’t beat anybody that day. You can’t worry about that. This is just practice. All runs are just practice. Some of them, eventually, might win you a trophy, maybe even a National event trophy, but it’s all just practice until you’re running for that National Championship jacket. Maybe even after you’ve won one of those, too.

What happens if you go over the limit on a race track? Worst case, you die. Bummer. Best case, you have an off and return to the pits for an inspection and maybe a time-out. You don’t even get to drive hard the rest of the lap. Rats!

Driving over the limit is really stupid at a track day. Nobody is going to kiss you at the end and hand you a trophy. Therefore, the fast way, trying to drive every moment at 100%, is not available to track junkies. They have to do it differently. They have to do it the slow way. The slow way takes a looooong time (as measured in track minutes) and lot$$$$$ of money, as measured in entry fees, travel costs, brake pads and discs, tire wear, extra brake fluid and engine oil changes, etc. And the kicker is that if you don’t do the slow way right you won’t ever get fast.

How can you drive hundreds of hours at the track and never get fast? I’m not totally sure, but from what I’ve observed you do it by driving consistently well inside your comfort zone. I suspect these folks steadfastly refuse the instructor’s pleading that you are now ready so please try going just a little bit faster. Probably, as soon as they can, they ditch the instructor and just circulate. Having fun. Some of them are really smooth, too.

Which brings up my next point: it’s pretty easy to be smooth at 90%.

What is the track junkie to do to get fast and develop top-notch car-handling skills? Other than doing 50 non-fun autocross events with such paltry seat-time and having to accept losing over and over again. Losing to teenagers in smoking, clapped-out Miatas with mismatched body panels and 300 HP less than you have. Losing to grandmothers. Losing to 85-year olds. Lots of losing in autocross!

You do what all the instructors say: gradually ramp up the speed while working on, wait  for it, Smoothness!

Why work on smoothness on the track and not the autocross course? Because what you really need to do is get sensitive. Trying to be smooth helps you do that, in the right circumstance, which is driving just a little bit out of your comfort zone. Not much out, just a little. Do that consistently and you improve.

If you drive on the track, you must drive below 100% if you want to own an operable vehicle at the end of the day, not to mention operable legs. But, if you drive at, say, an average of 95% you will actually vary around that by some percentage…let’s pick 3%, because nobody is perfectly consistent, certainly not the novice or intermediate tracker. That means you’ll wander around in the 92% to 98% range.

So, sometimes, for a brief moment, you actually are very near to the limit. If you are sensitive, driving for extended durations  at an average of 95% is close enough to get the feel for what the tires are doing and how weight shifts with every input you make and how that affects the level of traction front to back and left to right and how it affects what the car will do next and how it affects how you can execute the technique your instructor has given you, or the drill/practice/cornering method you have set for yourself. You will develop mad skillz, Bro.

On the autocross course you can use the fast way. Immediately push yourself to the limit and learn to handle it. What will you actually be doing? You’re understanding of the car’s dynamics will expand, you’ll anticipate events earlier, your sensitivity to what the car is doing will naturally increase, you will make corrections better, earlier and faster. You get instant feedback from all angles, including the time on the clock. Looking at data will show how much time each little mistake costs. If you want to win you stop making them. You will develop mad skillz, Bro.

You might even get to the point where someone will accuse you of being smooth.

One last thing. Is one way really faster than the other? Let’s say you do 25 autocross events per year for 5 years. That’s 125 days of your life. I think most people can develop quite good skills with that amount of autocross running, if they do it right.

Let’s say you do 25 track days per year for 5 years. That’s 125 days of your life. I think most people can develop quite good skills with that amount of track running. If they do it right.

Interesting: the two methods are not different in total time expended, but very different in seat-time.

Put in the time, either method, and you’ll get there. But, whatever you do, don’t drive the track at 100% (or you won’t last long) and don’t drive autocross at 95% (unless you’re OK with staying slow or you think of your tires like pets and can’t bear to torture them.)

me & vette small

At TAC/TVR #3                        Photo by Scott Budisalich






Data Analysis of Sharp Turn At Wilmington Pro-Solo

Just back from Wilmington, Ohio where I ran the Spring Pro-Solo. Great event with the usual close competition and great competitors in B-Street. This was my 3rd Pro-Solo, spread out over a 4-year period, and first Pro-Solo trophy, 3rd place.

B-street at Wilmington

Fig 1- B-Street Class at 2016 Wilmington Spring Pro-Solo


If you don’t know about Pro-Solo, it starts with a short drag-race between two cars lined up side by side. After 150 feet or so of full-throttle acceleration the cars peel off in opposite directions into mirror-image autocross courses. After the finish, the two cars cross over to the other lane and run the other side, again with a drag-race start. Then you swap sides two more times. Very, very intense.

The “amateur” or “old” drag race light-tree is used: a white light indicates the car is properly staged, then three yellow lights illuminate in sequence leading to the green go-light. The idea is to get in sync with the lights, learning when and how to launch, so that everyone leaves more or less at the same time, but no earlier than 0.500s after the green light. (0.500s is theoretically about the typical human reaction time to any signal.) Otherwise, people would simply guess the green light, most runs would be early and red-lighted (disqualified) and the winner would be the lucky one who managed to go right on the green without being early.

With the light-tree skill and experience are required to match your start time and technique with the car to get an on-time start (low, but not too low, reaction time) and best acceleration. Too much wheelspin and you’ll be slow, even if you started at the right time. Bog the motor and you’ll also be slow. Reaction time and time to cover the first 60 feet is recorded so you can analyze how good you’re doing. Any reaction time less than 0.500s (called a 500 light) results in a red-light and disqualification of that run. A good 60 foot time might be in the range of 1.9s for a car like mine when the start area has rubbered-in… I got one of those. A more normal 60 foot time for me was in the range 2.1s to 2.2s, so significant room for improvement exists. Too much wheel-spin at launch is my typical issue.

Each heat consists of four runs, two on each side of the course. Your final time is the best run on each side added together over three rounds, two rounds on Saturday and the third on Sunday. Three rounds times four runs per round equals 12 runs total, six on each side to determine the class winner.

Pro-Solo courses are typically shorter and faster than standard Solo courses, sometimes even less than 30 seconds if the area is small. These courses were 36+ seconds for B-Street and a bit unusual in that each side contained two very sharp, slow corners. These sharp corners were clear examples of age-discrimination. Both were more than 90 degrees, the second being a turn of an estimated 130 degrees. Many of the over-60 crowd (like me) can’t turn their head that far! I smell class-action lawsuit. (Just kidding, Mr. Herbst, course designer!) The options for taking that sharp corner are the main subject of this post.

A path plot from my data is shown in the figure below. This is only the left side course and the green start dot is placed near the end of the drag-race section, just before turning left into the autocross course. At that point the car is moving 30+ mph.

wilm course numbered

Fig. 2- 2016 Wilmington Spring Pro-Solo Left Side Data Paths

The plot shows three paths, one from each of the three rounds. There may be a little bit of GPS drift evident, but not enough to ruin the comparison. Light green is the best run from the 1st round, purple is from the 2nd round and red is the best run from the 3rd round.

I’ve marked the key turns as 1, 2, 3 and 4. Turns 2 and 3 were the sharp, slow corners I mentioned earlier. Turn 4 continued into the finish lights, so if you did it right, you never did get back straight until after the lights. Lots of fun testing your resolve and ability to control the car as you exited the 50+ mph, 7-cone slalom and negotiated this turn. After walking the course my plan was to stay tight, tight and tight on turns 1, 2 and 3. Sometimes I pushed out by mistake (entering too fast), but the plan was to stay very tight. In fact, the wide green path in corner 2 is a push-out caused by entering too fast. Later runs I fixed that.

After analysing data Saturday night, I changed the plan to: flow-thru 1, maintaining more speed and not trying to be close to the second cone that defined this sweeper, stay tight on 2, and not quite as tight as before on 3. My idea was that the entrance to the slalom after turn 3 is slow and short and therefore, 1) wouldn’t be much affected by more turning to get into it, and 2) didn’t afford enough of an acceleration zone to be worthwhile, especially starting from such slow car and engine speeds.

Not over-braking and flowing thru 1 to maintain more speed and engine rpms saved time down to turn 2 as compared to a tighter and shorter path… about 0.2 seconds. This should have saved time on both sides Sunday, but I red-lighted an otherwise mistake-free run on the right side, so I lost that improvement.

Staying tight and short around 2 was clearly correct. I had several different paths, due to mistakes, to compare one to another. I kept doing it as tight as I could on Sunday.

How tight was right around turn 3? That’s the question we are going to explore with the data. Turns out my first plan was best, but not by much. Though it certainly felt better to go faster around that corner, and was not any further distance, it didn’t quite pay off like I thought it would.

The figure below is a closeup of turn 3. It shows tight (green), not quite so tight (purple) which was a failed attempt to stay tight, and significantly wider and faster (red), which was done on purpose…

Wilm corner

Fig. 3- Wilmington Sharp Turn 3

… and here is what that corner looked like in reality:

wilm corner 3 annotated

Fig. 4- Approaching Turn 3

You approach at full throttle, figure out where to brake and what speed to brake down to, turn about 130 degrees and then accelerate while curving back to the right into the entrance to a long slalom.

The choice was this: whether to maintain the corner super-tight, which is almost always best, plus it gave a better entry to the slalom, or maintain more speed with a bigger arc, which takes a more direct path to the first slalom cone, but then sacrifice the slalom entry angle and acceleration to some extent. Because of the rather unique geometry of this corner as it led into the slalom, the various paths were all about the same total distance, so we can neglect distance effects. What does the data say? Here it is:

Wilm data 1

Figure 5- Turn 3 Data

The 340 position index is about the braking point. The LongAcc curves are all very negative by 350, indicating heavy braking. Looking at the top Speed trace you can see (if there were more gradation marks) that the minimum speed for the tight, green path is 22 mph, the next slowest is the purple path at 24.5 mph and the faster red path slowed only to 28.4 mph. So, we have three instances with different speeds around this corner and quite different paths.

Right of the vertical cursor line (set at 440 Position Index) on the Speed graph we see that the green path is higher (faster) than the others. The cursor is located where the green LongAcc trace turns positive, indicating acceleration. That’s one advantage of the tighter green path: it gets back on the gas earlier. In this case, that was made possible by starting from a lower speed.

Of course, what we really want to know is the time saved. This is shown in the DELTA-T traces on the bottom. The red path has been chosen as the baseline, so it stays flat while the other two fluctuate around it. We see that both the green and purple traces lose significant time during the corner, as much as .37 seconds. The time saved by the red path is 0.3s or more compared to the other two all the way out to the where the cursor is located, which is about where I begin to turn around the first slalom cone in each case. If we stopped our investigation at this point it would appear that the wider, red path saved significant time. The issue becomes clouded with what happens next, however.

Both wider paths have to continue turning longer in order to get around the first of the 7 slalom cones. The purple path almost, but not quite, makes up all the time lost to the red path by the time the car is half-way to the 2nd slalom cone. In fact, it might have made up all the time except for a drop-out in acceleration that’s evident in the LongAcc trace at about 465 Index. Probably the rear tires slipped out a bit.

By the end of the data trace the green path has saved almost 0.1s as compared to the red path. This isn’t a lot, but there are some other facts we must consider:

1) the grip was the least during the first round (green trace) and best during the 3rd round (red trace). So, if I’d continued to always take the tight path the time saved by the tight path probably would have been a little more because the cornering speed would have been higher at the same tight radius.

2) a significant slow down is evident in the red Speed trace at the 450 position index. The car slows back down to 28.5 mph a second time in order to negotiate the first slalom cone turn, which is sharper due to being “out of position.”  This is what really hurt the wider, faster red path.

Conclusions: for my car, with its particular grip and acceleration characteristics, it didn’t much matter how I took this turn! There’s hardly any difference in the Delta-T once you take the first part of the slalom into account. What appeared at the time to be better, namely a wider, faster turn with a more direct path to the slalom did not actually save any time. On the other hand, it appears to have cost only a very small amount.

What about for other classes and cars? Well, a faster accelerating car would gain more accelerating into the slalom. So, tighter would have definitely been better. A weakly accelerating car might very well have saved time by not staying super tight and maintaining more speed, more like the red path.