2020 Lone Star Le Mans - FIA WEC 6H of COTA Engineering Notebook

The first WEC round of 2020 amongst months of discussion and news surrounding the future of Sportscars brought with it some focus on the present. 
This round replaced the Interlagos race that was cancelled due to financial issues with the race promoter, resulting in a return to the Circuit of the Americas for the first time since 2017.



This article will follow the usual format, focusing on using top laps to show what each car proved it was capable of performing, giving an indication of performance of the chassis, driver, tyres and setup.

LMP1

Going into the race, Rebellion needed to make up for lost ground in Bahrain, where despite having the fastest car, they lost out to Toyota after necessary repairs.The pace in Bahrain gave a prediction of what to expect at COTA considering Toyota were given more handicap in the break - On paper Rebellion should win a clean race at COTA.
Rebellion's Handicap Coefficient was less than halved for COTA, from 0.25 to 0.1 s/km. This equated to 1.36s at Bahrain and 0.55s at COTA.



Rebellion have gradually improved their lap time consistency all season, giving them the ability to hold off a pace advantage compared to the Toyota TS050s.

The Team LNT Ginettas would have fared well too thanks to the lack of Handicap, because they fell over 40 points from the championship leader. The Rebellion Gibson platform would likely overcome this half second handicap however.

Unfortunately they wouldn’t make the trip over to the USA just yet, preparing for an assault at Sebring. Hopefully this will bring updates to the G60 platform and an improved reliability and performance level.

LMP1 Updates

Due to this round being a freight round, the logistics of sending new parts is made more difficult, and thus entries are less likely to have significant bodywork updates. No changes to the cars were noted since Bahrain. The circuit characteristics are similar to the previous rounds, so the requirement of significant modification/re-homologation is not present.

LMP1 Success Handicap

As mentioned before, at Bahrain, Rebellion clearly had the fastest car. Without the initial setbacks they could have won on pace, with the higher efficiency of the Toyotas pegging back the non-hybrid in the pits.

After Bahrain, the Toyota win enlarged the gap to Rebellion in the championship, thus giving Rebellion less of a handicap for COTA shown below in the Success Handicap table:

I believe this is the right angle to proceed with balancing cars wildly different in technology and design as the efficiency, reliability of the car and performance of the team as a whole is included, rather than just using the top 60% of lap times in the GTE BoP algorithms - balancing top laps doesn't cover the whole picture!

To improve this model, I would however use the time gaps at the end of races instead of/in addition to the championship points currently used. A time gap per km travelled may prove useful to compare with the s/km handicap which governs theoretical lap pace. Using this and if tuned well, the handicaps would not oscillate the field as much as what we have observed and also converge towards each other. If weighting of championship points and time gaps are done well, there should be a closer performance and closer racing but not a complete balancing like in GTE.

The plot above shows how unstable the coefficients are over the season. If they trended towards a value with any stability, the previous three races would not have wild changes between them as the body of data increases. Toyotas trading wins have swapped the championship lead several times, and therefore the handicap coefficient several times. The recent instability in Rebellion handicap was from the Bahrain poor result.

Cars of the same make can be more likely to race against each other in this hypothetical format, so the Toyotas wouldn't have such an obviously artificial gap especially when compared to being so close all Superseason. A time gap over a race can be helpful to directly converge a class, but also it can be seen as penalising time savings with a better pit crew for example. Looking at the big picture, it's a hard pill to swallow but one that should be considered with the viewer in mind, allowing this format of racing to have a future.

LMP1 Pit Time

Over the several stops made, the comparison between each car’s time spent in the pit lane can be compared.

The efficiency gains the TS050 has over the Privateers is notable, and may save them a stop in the longer races. At the shorter races, it allows them shorter refuelling time, as there is significantly less fuel needed, but the duration isn't enough to save a journey through the pits. The pace difference between cars overcame this pit lane advantage at COTA, however an updated and much closer success handicap should make pit lane time more important towards the results. I believe the savings made at COTA show the TS050s could take one less stop than the Privateers.

Success Handicap for Sebring

So, looking forward to Sebring, what is changing with the success handicap levels. 

Using the formula in the regulations, Rebellion will have 1.36 seconds added to their theoretical lap time (0.81 up from COTA). That should bring them closer in line with the faster Toyotas. The TS050s will again be split in handicap levels; roughly half a second split between them. This gap translates well towards gaps in the race, however the magnitude of the gap is not predicted well by the success handicap, due to the many variables at play - races are not run on spreadsheets!

What of the Team LNT Ginettas for Sebring? This is unknown. The regulations have not stated if there is a handicap applied if a full season entrant misses a round. This made perfect sense, as the threat of a potential penalty would encourage entries to complete the full season of races. If you know the cost and impact to performance, you can budget for it! And, speaking of cost, one missed round fee might even be outweighed by the savings from not shipping your car, team and equipment across the Atlantic.

There are several avenues the FIA WEC can go down here for the success handicap, each affecting how the Ginettas will perform. As they scored no points since Bahrain, they shouldn’t have any additional handicap as per the success handicap model relative to points.

The organisers can penalise the Ginettas each with, let’s say, a race win’s worth of points (25) to the handicap calculator, but this still makes them fall well below the 40 point cap from Toyota (in this case still over 60), so no handicap would result.

If the FIA WEC wishes to penalise Ginetta, then they would need to apply several race wins worth of points to the handicap system…

I say let them race with what they have in the trim from Bahrain, and see what they can do on the bumpy surface, hopefully close to lap record pace on a clean tour of the airfield. The longer distance reduces the confidence in a victory on pace anyway, so giving them a leg up will be a good thing for the show, something lacking recently in top class racing.

Sebring Circuit Characteristics

Sebring has several long straights, allowing the non-hybrid machines to stretch their legs.

I expect the Ginettas to be strong here on the several straight sections helping the passing of traffic.

The bumpy surface will test these cars to breaking point, and attrition is not something I can comment on in advance so much considering the LMP1 reliability has been relatively high compared to the history of the class. The Rebellion's Gibson engine is already a shaky thing though...

LMP2

I will be using the same comparison method as above in P1. The plot below shows the top lap times from each car in ascending order.

LMP2 at COTA was a massive result from the Michelin teams, showing times far faster than the Goodyear competitors - between 1 and 2 seconds faster a lap in the case of Racing Team Nederland. The JUMBO Supermarkets sponsored car was by far the fastest on raw pace, the team pushing hard to give their Bronze driver (Frits van Eerd) the largest gap possible to work with near the front of the race. Cool Racing were close behind as RTN settled into their consistent race pace. Further back were the Alpine crew and the United crew, very closely matched! It was a surprise to see these teams close together, as United has usually been closer to the front of the class (see Bahrain!), and the Alpine was usually one of the slower Oreca supplied cars. Hopefully this is a sign of things to come for Alpine in the run up to Le Mans after a rocky start to the season and a new driver lineup.
The two JotaSport-run Oreca 07s on Goodyears were closely matched across the plot. The consistency was very good, however their pace was not. High Class (#33) recently switched to Michelin, so I am not surprised they weren’t competitive on pace, as were the Dragonspeed crew, here as a one-off. Cetilar improved, but were still several seconds off the fastest laps in the Dallara.

At Sebring I hope the Goodyear cars improve, as they were the fastest last time out a year ago. High Class should improve and become more competitive. The larger temperature variation as the race goes to night should add an extra flavour to the LMP2 tyre war. Which teams will make the most of the daytime heat and cooler night conditions?

LMP2 Amateur Driver Performances

As usual I will be comparing the Amateur drivers in LMP2; how they performed as this is a major factor in the outcome of the class results. For example the gaps found here are much larger than the gaps found between Pro drivers, even though the drive time considered is much less.

Antonin Borga was the class of the field cementing his claim as the best Silver in LMP2 racing at the moment, worldwide. Unfortunately his Cool Racing entry is held back by the drive time of Alexandre Coigny, himself a Bronze, further back. Behind Borga (around half a second behind) was Pierre Ragues, Phil Hanson and Gabriel Aubry. A good showing for the Alpine Amateur hopefully turning a corner after moving from Duqueine in ELMS. Anders Fjordbach impressed on new tyres with good consistency. Behind this group (a second behind) was Roberto Gonzalez on Goodyear. This was a surprising performance considering his competitive performances with Jota Sport and Dragonspeed in the past. A good showing for Roberto Lacorte in the Dallara put him as the best Bronze on this plot, however he had around twice the drive time as any other Am, giving him more laps to find clean ones and get some good times in. This is a foolish tactic for competition, as you ideally want the Am in for the least amount of time as possible. On the other hand, the gentleman paid his way for this drive, and deserves to enjoy his time in the car. The Bronzes behind were Henrik Hedman, Mark Patterson, the aforementioned Coigny and dropping back considerably was Frits van Eerd in the Racing Team Nederland car. The improvement of Mark Patterson here was remarkable - at Bahrain with more drive time, was over a second behind Frits, who himself was a few tenths off Lacorte. Could this be down to the switch from Goodyear to Michelin, with the latter being easier for Amateurs to reach their true potential? Gonzalez’s swap to Goodyear could confirm this in the other direction…

GTE Pro Performances

COTA brought the addition of Corvette to the WEC paddock in the form of the new C8R machine giving us a look at how this new car shapes up against WEC competition leading up to Sebring and Le Mans.

Looking at the top laps, Aston Martin had good consistency at this round. Their fast laps at the bottom of the plot were set at the start of the race, when the 95 and 98 were running Noah’s Ark at the front in clean air, with no LMPs passing them giving clean lines in each corner. Porsche had a section of good laps with the 92. Ferrari had one good entry with the 51 closely matching the 95 Aston. Quite a stunning result proving a benefit of BoP! Unfortunately the 71 was relatively miles back. This must have been driver or setup problems, as the 51 showed the car had pace.

The Corvette team was miles off the pace learning the new car. Apparently the engine was incorrect in this car. Potentially a homologation timing issue and therefore using an old development unit? Hopefully their issues will be resolved for Sebring. One reason for the pace being low was strategy as they had one fewer pit stop than the rest (4 instead of 5). They had the largest fuel tank size (102L) and had the lowest weight. The single air restrictor cross sectional area was 6% lower than the Porsche’s pair, but a single restrictor is more effective as there is less boundary layer choking effects with a single restrictor setup - the boundary surface to cross section area ratio taken at the narrowest point. I do not see this as a BoP issue that was claimed by the drivers and many members of the Sportscar community. It was potentially a strategy ploy to go longer on fuel with the larger tank, and/or limping along with a handicapped car. The trouble is it left them finding it hard to pass GTE Am competitors, even with the Ams in the other cars! More on this below...

GTE Pro Pit Stops

The Aston Martin 97 car had the least time in the pit lane, closely followed by the 92 Porsche 4 seconds longer. It’s impressive considering the top 5 cars in the class were within 17 seconds of each other over 5 stops!

Corvette were much slower with their stops, up to 10 seconds each time. This could be down to the longer fuelling time if they elected to fill to the brim their C8R (along with the more fuel efficient fewer stops strategy), or the fact the crew are inexperienced with WEC pit lane regulations, and the lack of a wall in their way…

GTE Am Performances

GTE Am has success ballast taking most recent wins and championship position into account. Running into the race the table below shows the ballast to be fitted to each vehicle where applicable.

This clearly translated into the handicapped performance of the 57 Porsche considering the driver talent - shown in the plot below. They did however have some reliability issues, so the time available to set fast laps was reduced. The AF Corse Ferrari moved its ballast well, putting together some competitive lap times, alongside the 77 Porsche. The two Aston Martins were the other two cars held up with ballast, nestled within the pack. Their times were very consistent however, showing the vehicle’s dynamics can handle the weight giving a stable and predictable car.

The 70 MR Racing Ferrari was again quick with their best laps. The rest of the class filled a tight block within around 3 tenths of each other, except for the Clearwater who fell away significantly. So, when I said there was more to the Corvette story? It turned out to be the case that it was slower than nearly all of the GTE Am machines!

GTE AM Silver Driver Performances

The times when the Silver drivers were in the cars start to provide diversion in the results. Ferrari young driver Nicklas Nielsen was the star of the show here despite 10kg of ballast. Kei Cozzolino was fast, but less consistent followed by the Aston Martin Silvers of Ross Gunn and Charles Eastwood respectively. It is no surprise that Nicklas and Ross Gunn have futures as Pros if their lap time plots are as flat as they were in COTA, showing they can repeat lap times nearer their best for longer periods.

Half a second off Nielsen was Andrew Watson, Riccardo Pera and Felipe Fraga. Laurens Hörr replacing David Heinemeier Hansson in the 56 Project 1 Porsche was an improvement on the Dane with less time gap to the top Silvers, however I was expecting more. Hopefully he gets up to speed with the new-to-him GTE for a charge at the overall title again.

GTE AM Bronze Driver Performances

Arguably the source of the most important metric for GTE Am racing, and the identity of each entry, is the Bronze driver for each car.

Ben Keating didn’t stream away at the head of the field this time out, so it was much more competitive here at the front! Despite Perfetti having the best laps, his consistency was lower so dropped off a little into the next four. They were Salih Yoluc, Paul Dalla Lana, Francois Perrodo and the aforementioned Keating. Each of these drivers were within a couple of tenths of each other here in the plot showing how competitive the class can be with Success Ballast. 4 tenths behind this group were Bonamy Grimes, slowly but surely improving in the Ferrari and GTE stalwart Christian Ried. Another driver who has improved this season is Michael Wainwright, this time with a little ballast.

Success Ballast for Sebring

Acknowledging the impact of ballast to GTE Am, the table below shows what to expect at Sebring. AF Corse dodged some kilograms by finishing 4th two races in a row, so maintain a good championship position, but lines up an assault towards a race yielding 1.5x points. Both Aston Martins have identical ballast hopefully adding to their competitive fights on track. The Project 1 Porsches have ballast also, with 5 kg on the 56, and 15kg on the 57. Gulf Racing will still have 5kg of ballast, but they are not expected to be as competitive as the above entries. I think all cars with ballast are the main competition for Sebring, could another team like Dempsey Proton join in the fun without any handicap? Regardless, I think the Astons will be the cars to beat. The colder nighttime track temperatures might suit this car, as it is historically better in cooler/wetter conditions.

So, after getting 3 out of 4 class winners in my previous article, I’d better try and get a streak going! For Sebring, predictions are more risky thanks to the increased reliability concerns from the bumpy track surface. I will go with #1, #22, #51, #83.

- Oliver Trewavas