How to decipher on-track data for faster lap times...

Velocity/Distance: Information’s Constructing Block

First, let’s discuss what we’re going to take a look at mostly, which is both a pace/distance graph or a pace/time graph. A pace/distance graph shows the pace of the automobile on the y-axis and the gap the automobile has traveled on the x-axis. A pace/time graph replaces that distance axis with time. Mainly, they’re each plotting a automobile’s pace alongside its path across the observe. 

You’ve most likely already found out that every kind of graph will produce barely totally different outcomes. Displaying two laps on a pace/distance graph will overlay the laps instantly on high of one another, permitting you to learn the pace of the automobile at particular factors on observe no matter when it occurred. The pace/time graph will show the laps as they occurred in time, and usually that may end in one graph being shorter than the opposite.

When evaluating two laps in the identical automobile, a pace/distance graph is mostly extra related. You’ll be able to immediately see pace variances in particular corners–all the way down to precise factors by means of these corners–and simply examine them to one another. 

With a pace/time graph, the diverging traces present a reasonably good concept of the place you’re gaining time at particular factors on observe, together with how these positive factors have an effect on pace at subsequent elements of the observe. A pace/time graph is often an excellent object lesson in the truth that nailing one nook pays dividends not simply in that flip, however for portion of the observe past that–principally till you screw up once more.

For fast reference, we’ll principally attain proper for that pace/distance graph, however what precisely will we be ? Sometimes, a pace/distance graph appears like a triangle or sawtooth wave, with alternating peaks and valleys exhibiting the automobile accelerating and decelerating because it negotiates the straights and corners. For many vehicles, the rising a part of the wave is much less steep than the falling half–practically all vehicles can brake more durable than they speed up, in order that they lose pace quicker than they achieve it–and fixed pace sections show as horizontal traces.

Let’s begin our fast scan by these peaks and valleys, as a result of there’s quite a lot of info to glean simply from how the up slope turns into the down slope. 

On the high of the graph, we see a graphic illustration of our driver lifting off the throttle and making use of the brakes to decelerate for a nook. Ideally, this a part of the graph must be very sharp: acceleration rising to a peak after which immediately turning into deceleration. 

For those who don’t see a pointy peak, just a few conditions could be costing you pace. An acceleration curve that plateaus earlier than quickly dropping is indicative of a driver lifting the throttle early and coasting towards the braking zone. Naturally, practically all vehicles could have acceleration curves that develop into much less steep as pace rises and the automobile wants to beat more and more taller gearing and better air friction. However these flat traces earlier than the braking zones are telltale indicators of early lifts.

Conversely, a graph that steadily rises however then begins dropping in a convex curve earlier than quickly angling down signifies a very gentle preliminary brake utility. 

Irrespective of which aspect of the height that gradual curve falls on–and particularly if it’s on either side of the utmost velocity–it’s a purple flag. Fast laps don’t look after inaction or coasting, and a pleasant sharp peak on the high of that velocity curve is a significantly better indication that you simply’re wringing the max efficiency out of the automobile.

Now let’s go to the underside of that curve. The fundamentals listed here are related, however the nuances develop into extra, nicely, nuanced. The trough of a pace/distance curve exhibits the second the motive force stops decelerating and transitions again to throttle to speed up by means of and out of a nook. 

These troughs, when driving inputs are correctly executed, will observe some patterns. One generalization we are able to make is that slower corners with a single apex have a tendency to point out up as sharper factors. It is a results of decelerating towards the turn-in level, setting the arc, and throttling out. Extra advanced corners have–you’ve most likely already guessed–extra advanced pace traces, however we’re coping with generalities earlier than diving too deep into the weeds.

One other generalization we are able to make is that quicker corners have extra rounded troughs. In these corners, you’re slowing extra gently, managing that weight switch and cargo on the tires, then accelerating by means of and out with much less thrust, as you’re seemingly in the next gear. 

Pink Flags

With various kinds of corners naturally having different-looking traces, what are a few of the purple flags we are able to search for? Nicely, the primary and best to identify are spikes. A downward spike after the curve that has bottomed might be a sign of a too-fast entry–both due to an excessive amount of velocity or too little confidence–leading to an abrupt elevate or perhaps a brake utility after turn-in. 

On the climbing portion of the graph, search for upward slopes that all of a sudden degree or plateau–even simply momentarily. This may be indicative of lifts after the apex, and even of wheelspin as acceleration pauses for an on the spot.

What concerning the creamy center of these traces? Is there something we are able to study from these lengthy slopes within the acceleration and braking zones? Yep, lots, and most of it can come from the steeper, braking aspect of the hint.

Ideally, the deceleration hint ought to look pretty straight, exhibiting a relentless fee of deceleration because the automobile approaches the nook. Automobiles with a lot of aero could have a naturally steeper preliminary deceleration curve, as the extra downforce at larger speeds permits for extra traction and decelerative drive. Basically, although, that line must be straight–or a minimum of a constant, possibly barely concave curve. 

Simply as we noticed on the acceleration aspect of issues, any areas of sudden flattening or noticeable bumps are trigger for investigation. Steadily, wheel lockup seems as a fast flattening as brake strain is momentarily launched to get the wheel turning once more. Overly aggressive ABS intervention can manifest as a slowing deceleration fee, and sloppy heel-toe work can present up as something from a small, jagged blip to an entire shift within the deceleration fee and a change within the curve’s form.

Acceleration traces, then again, usually look extremely convex–besides when the automobile has tons of energy and traction. Acceleration fee tends to drop off at pace as reducing gear leverage and growing drag struggle horsepower. Nonetheless, there are some things we are able to study, even after the all-important nook exit.

First, a look on the whole hint can reveal some downside areas–most notably, anyplace the road goes horizontal. Even the longest, most geometrically constant corners are likely to have entry, apex and exit factors, so any horizontal traces must be analyzed for potential positive factors. Sure, lengthy turns just like the Carousel at Street America or the Karussell on the Nürburgring would require some space of pace upkeep, however basically, should you’re seeing a horizontal line, you may need to ask why it’s there within the first place.

And let’s take a look at shift factors. In vehicles with handbook transmissions, a shift level usually shows as a momentary flattening of the acceleration curve. Throughout these moments when the driveline has been utterly decoupled by the depressed clutch pedal, no acceleration is feasible. 

Whereas there isn’t a lot you are able to do to remove these gear modifications, you may study them for additional positive factors. Is your two-three shift, for instance, longer or shorter than your three-four and even four-five shift? 

As soon as a shifting plateau ends, does the road return to a constant rising hint, or is there a wiggle within the curve? That wiggle can reveal a mistiming of throttle utility when reengaging the clutch. Or possibly you’re reengaging the clutch too abruptly or too slowly. 

Going Additional

Now we all know how one can glean a ton of knowledge simply from a pace hint, however what occurs once we add extra sources of information to the combination? Can we nonetheless get fast driving suggestions between periods?

Nicely, sure. 

Whereas amassing extra knowledge definitely ups the complexity degree, a few dynamic inputs can present a 1000-foot view of the state of affairs. We discover that one of the best instrument for that is the friction circle, which is generated by plotting lateral and longitudinal g-loads on a round graph. 

On a friction circle graph, the x-axis signifies lateral g and the y-axis signifies longitudinal g. This knowledge might be considered both as a transferring dot over time or as a cloud of dots taken at a number of pattern factors all through a lap. 

The important thing purple flag: any exercise in the midst of the circle signifies that the automobile isn’t doing a lot of something. Likewise, the friction circle supplies an effective way to gauge your transitions out and in of corners, as ideally the dot indicating the g-loads is using across the exterior of the circle, indicating that any loss in longitudinalg is changed with a achieve in lateral g–and vice versa. If the dot is transferring by means of the middle of the circle between longitudinal and lateral masses, it’s signal that brake or throttle purposes aren’t easily mixing with the corners’ entries and exits. 

We’ve hit practically 1800 phrases at this level and we’ve barely scratched the floor on this matter. The takehome message: You’ll be able to pull sensible driving suggestions from even a cursory look on the easiest of information sources.