IMSA Race 2018 Mobil 1 Twelve Hours of Sebring presented by Advance Auto Parts - Mar 14-17

[Ospi]

Originally Posted by FormulaFox

Regarding BoP levels...

http://results.imsa.com/Results/18_2...by%20Class.PDF
^ Fastest laps of the weekend over all sessions.

Notice the fastest LMP2 car is in sixth, nearly (but still less than) a full second off of the fastest DPi. But notice as well that...

1) The quickest DPi is 0.4s faster than the second quickest - this speaks volumes for the effects of setup.

2) That LMP2 was faster than one of the Acuras and both Mazdas - this speaks volumes for how the big the gap actually is.

Clearly, the DPis have a BoP advantage, but it's FAR closer than it was this time last year, and it is feasibly possible that a particularly good team could still find a setup and driver pairing to match the DPis, longshot though that may be.

In other words, although only one LMP2 driver managed to do so, the fact remains a lap time was posted that was right in the middle of the DPis. That simply wouldn't be possible if the BoP was as far off as is being claimed.

Put simple, the BoP needs work, but it's not the utter disaster many believe it to be.

A single bonzai lap doesn't say much though, you need to consider averages correctly if you want to build useful data, for example best 5 lap avg, 10 lap avg, 30 lap avg etc which filters out unreliable data which can be extremely contextual.

[Ospi]

Cheap and nasty graph showing the averages:



Result being that the quickest P2 overall was 0.8s slower on average (on all 3 metrics) than the mean of all DPi and close to 0.4 slower (20 lap avg) than the slowest DPi. These numbers filter out the slower drivers and only compare the best each car has to offer so they paint an interesting picture when it actually counts in the race.

I'm sure IMSA will adjust accordingly and we'll have some P2's in amongst the action throughout the season though but it's clear imo that adjustments do need to be made if they're genuine on the performance parity.

[joeb]

Originally Posted by champcarman

Slightly off topic, but how do most people rate the chances of the IMSA/WEC double header at Sebring 2019 actually going ahead? I thought there were representatives from the ACO and FIA there on the weekend to discuss the logistics etc so I suppose we will have to be patient. I am hoping to make a holiday in Florida next year for the St Pete Indy/ Sebring double and an IMSA/WEC double header could be the decider. If this is covered in another thread please excuse my lack of diligence.

All outward press says this is happening as scheduled, but there are some folks who are skeptical.

Originally Posted by Ospi

Cheap and nasty graph showing the averages:



Result being that the quickest P2 overall was 0.8s slower on average (on all 3 metrics) than the mean of all DPi and close to 0.4 slower (20 lap avg) than the slowest DPi. These numbers filter out the slower drivers and only compare the best each car has to offer so they paint an interesting picture when it actually counts in the race.

I'm sure IMSA will adjust accordingly and we'll have some P2's in amongst the action throughout the season though but it's clear imo that adjustments do need to be made if they're genuine on the performance parity.

That is a good representation of the individual cars abilities. It reminds me of the GTEins diagrams that show individual driver performance as well. That 77 Mazda was flying!

[RedSquirrel]

Originally Posted by Ospi

Cheap and nasty graph showing the averages:

Adding drivers of the calibre of Rast and Jarvis has really transformed Mazda, nearly as much as dumping Speedsource. The #55 would be right there too probably if Pigot was as fast as Ticknell and Bomarito.

Originally Posted by Matt

...and they got beaten - twice - by that "vanity side project" with Jon Bennett as one of the drivers.

You can discount Bennett this weekend really as he had his driving done before half distance and so before the spate of safety cars that allowed CORE to get back the two laps they lost while he was driving. So United were really beaten by Romain Dumas and Colin Braun. Which is reasonable.

[FormulaFox]

Originally Posted by Ospi

A single bonzai lap doesn't say much though, you need to consider averages correctly if you want to build useful data, for example best 5 lap avg, 10 lap avg, 30 lap avg etc which filters out unreliable data which can be extremely contextual.

You need to consider average lap data when trying to account for exactly which matters affected race performance, not when you're trying to gauge how close the BoP actually is.

The outright top speed over a single lap at the limit speaks VERY loudly about how close the BoP is. If a car can be within 0.1s of the next car over a single lap, then the cars are very reasonably balanced.

But if the BoP is bad, then the slower cars will never be close to the leaders at all. Not over one lap, two laps, five laps, or whatever you want to count. The absolute fastest race laps of all the cars over the weekend speaks the loudest over whether or not the BoP is close enough than any average speeds over multiple laps can. There are too many variable effect things over multiple laps, but the fastest lap can be taken as an example of the potential maximum performance of the car.

[chernaudi]

Maybe we need to remember 2014, when the LMP2 cars could get close to or even be faster than the DPs on a flying lap, but in the race once the DPs got in front they often pulled away because of better top speed which gave them better ability to work traffic.

Same thing with the Audi R10 vs LMP2s in the ALMS. Only better fuel mileage saved the day a lot of times for the Penske Porsches.

[Purist]

I also wonder how close the teams actually were to the allowed BoP maximums. And let's face it, the factories can more easily afford to blow an engine than the privateers; so the latter will likely blink before the former in terms of dialing back the settings in order to preserve reliability.

Also, I wonder if Mazda was doing the same thing to an extent, and getting that increased mileage out of it as a benefit.

And though I don't see it happening, it would be very interesting to see the Penske Oreca trotted out again to get a straight-up performance comparison.

When I looked over the page, I think all the Prototypes had their fastest lap between a 1:49.0 and a 1:51.0; so that's not exactly a massive disparity.

Is there a listing of the trap speeds to have a look over that?

[Matt]

Originally Posted by Purist

I also wonder how close the teams actually were to the allowed BoP maximums. And let's face it, the factories can more easily afford to blow an engine than the privateers; so the latter will likely blink before the former in terms of dialing back the settings in order to preserve reliability.

Also, I wonder if Mazda was doing the same thing to an extent, and getting that increased mileage out of it as a benefit.

And though I don't see it happening, it would be very interesting to see the Penske Oreca trotted out again to get a straight-up performance comparison.

When I looked over the page, I think all the Prototypes had their fastest lap between a 1:49.0 and a 1:51.0; so that's not exactly a massive disparity.

Is there a listing of the trap speeds to have a look over that?

http://results.imsa.com/Results/18_2...Qualifying.PDF

Fastest for each car through Q.

[Coach Ep]

Originally Posted by champcarman

Slightly off topic, but how do most people rate the chances of the IMSA/WEC double header at Sebring 2019 actually going ahead? I thought there were representatives from the ACO and FIA there on the weekend to discuss the logistics etc so I suppose we will have to be patient. I am hoping to make a holiday in Florida next year for the St Pete Indy/ Sebring double and an IMSA/WEC double header could be the decider. If this is covered in another thread please excuse my lack of diligence.

Neveu, Fillon, Beaumesnil and other senior WEC/ACO personal were all there, even said bonjour to them when they visited turn 17 to have a close look trackside (giving them the opportunity to mock the Mini's in Conti Challenge bouncing their way all the way thru the turn!) They did plenty of laps in several IMSA cars and spend quite a bit of time on the deck of the Weathertech VIP tent right before turn 17. Never saw them in Scott Atherton's presence though. The discussions were scheduled for Sunday (yesterday) I believe.

I'm fairly convinced the double-header will be on next year, just not sure about a lot of details/issues that need to be ironed out.

[carbsmith]

Originally Posted by Purist

the factories can more easily afford to blow an engine than the privateers; so the latter will likely blink before the former in terms of dialing back the settings in order to preserve reliability.

The Gibson teams don't have any particular say in the matter. The engines are leased and they're stuck with the engine mapping Gibson sets to make them run long enough to make the lease price the ACO set viable. That's the whole reason DPis with bodged in stock blocks are able to be faster at all.

[EffectiveSprinkles]

Originally Posted by FormulaFox

You need to consider average lap data when trying to account for exactly which matters affected race performance, not when you're trying to gauge how close the BoP actually is.

The outright top speed over a single lap at the limit speaks VERY loudly about how close the BoP is. If a car can be within 0.1s of the next car over a single lap, then the cars are very reasonably balanced.

I would say this is simply completely untrue. If only because you have no idea about the circumstances of that one outlier lap. You seem to want to argue the BoP was 'very close' but provide zero evidence and ignore evidence others present.

[champcarman]

Originally Posted by Coach Ep

Neveu, Fillon, Beaumesnil and other senior WEC/ACO personal were all there, even said bonjour to them when they visited turn 17 to have a close look trackside (giving them the opportunity to mock the Mini's in Conti Challenge bouncing their way all the way thru the turn!) They did plenty of laps in several IMSA cars and spend quite a bit of time on the deck of the Weathertech VIP tent right before turn 17. Never saw them in Scott Atherton's presence though. The discussions were scheduled for Sunday (yesterday) I believe.

I'm fairly convinced the double-header will be on next year, just not sure about a lot of details/issues that need to be ironed out.

Thanks for that information.

[Deleted]

Ya that's pretty interesting, thanks Coach.

By the way, if there is one thing IMSA still does better, it is the packaging of the weekends and support race spectrum, I hope the ACO heads took side notion of that if they were there on Friday (?)

[Maelochs]

I think, no matter how many laps we look at, it is pretty easy to see that P2s didn’t get favorable BoP vs. DPis.

I am not too worried. BoP tends to change for every race.

On a more cynical note … IMSA knows who pays the bills, and they know that having manufacturers involved, however tangentially, is important to the series. No one wants to see the P2s bail … but most P2 teams (Perf Tech, Core, JDC-Miller) are Pro-Am efforts and Businesses, which make money renting seats in the Big Show. They will always be around.

IMSA doesn’t depend on UA or Rebellion for its legitimacy. It depends on Cadillac, Acura, and Nissan … and now Mazda (finally.) Hate to look at it that way, but …

But I am sure BoP will get many adjustments … and by the time Daytona and Sebring 2019 roll around, whatever happened this year will be irrelevant.

All the carping in the world cannot destroy what was a pretty exceptional race. In fact, a Pair of exceptional races.

Daytona was an old-school endurance race, where attrition and the ability to repair cars under green made a difference. I loved it. Apparently a lot of people did.

Sebring went five hours with two cautions … and one was for a flying canopy, not a car. It was sad that a bunch of numb-nuts cautions stacked up later, but I cannot think of too many times the series didn’t get things rolling again pretty quickly.

All in all, racing dominated the race, not endless caution periods. And in all three classes the outcome was undecided until the last 45 minutes or later. In a 12-hour race, to have more than 11 hours of hard-core competition is pretty awesome.

And even then, with Derani’s low-fuel light, the race could have gone a different way in the last two minutes.

Nothing is ever perfect, and people who hate themselves can always blame something outside of themselves. BoP wasn’t perfect, the temperature was two degrees too high, there wasn’t enough breeze, there should have been more clouds ….

It seemed to me BoP was pretty much spot on in GTLM, GTD, and DPi. The P2s needed 10 kg less ballast or something (since they can’t play with tuning.) I really liked that the Mazda had pace and efficiency … I love watching teams play strategy options.

I am glad the Caddys didn’t dominate—funny how no one seems to recall that pretty much only Cadillacs won pretty much everything for the past three years except when they crashed. I guess Nissan and Acura sat down with series management and said, “If you want us to remain …. “

Also great seeing Core win Pro-Am and fourth overall. I have always liked that team. Just a personal pleasure, doesn’t affect the race objectively.

But come on … three-way fights in three classes coming into the last hour of an endurance race … and we are looking for negatives?

After another three races we will see how well IMSA can manage BoP (Long Beach will be tough, as Sebring and Daytona were tough … very unique tracks.)

Everyone is different and I don’t want to invalidate anyone’s views … but if, after a race like Sebring 2018, you cannot bask in the afterglow for a couple days … maybe more fiber in your diet or something, I don’t know.

[Coach Ep]

Originally Posted by Chiana

Ya that's pretty interesting, thanks Coach.

By the way, if there is one thing IMSA still does better, it is the packaging of the weekends and support race spectrum, I hope the ACO heads took side notion of that if they were there on Friday (?)

The ACO hot shots were there all week(end) or at least from Thursday onwards when I spotted them. It wasn't a secret mission obviously so no need to go undercover or whatever.

Next year we won't see the Historics at the event as there is the big show to fit in and I fully expect IMSA to run their 3 support series (Conti Challenge, Protos and GT3s) like they have been doing for a number of years now. Should make for a very busy schedule next year without much rest for us workers...

[Bill38]

Is there a web site that has the hourly standings of the each car in this years 12 hour race?

[NSX_LeMans]

Originally Posted by Bill38

Is there a web site that has the hourly standings of the each car in this years 12 hour race?

imsa.alkamelsystems.com?

[Matt]

Originally Posted by Bill38

Is there a web site that has the hourly standings of the each car in this years 12 hour race?

results.imsa.com

[fergus_r]

Back from my second trip to Sebring. I generally thought the racing was far better than last year- both the supports (especially the Porsche race on Friday) and the main event itself were all very good.

It leaves a little to be desired as a spectator facility- some key corners like Turn 1 and Turn 17, two of the most spectacular, are difficult to view from due to various reasons, and they STILL haven't sorted out a PA for the circuit- seriously, for a big event like this I find that unacceptable. Signal was too poor/non-existent to load up IMSA Radio on the phone on race day.

I thought the Historics were a great addition and filled what would have been empty space very nicely. Great mix of cars and a decent number of them, with some good racing and some interesting lines through the hairpin!

[Maelochs]

Originally Posted by fergus_r

Signal was too poor/non-existent to load up IMSA Radio on the phone on race day.

major personal peeve. I can't get the FM broadcast, the web broadcast, T&S ... anything while walking around the track.

Luckily the cars sound good.

[fergus_r]

Originally Posted by Maelochs

major personal peeve. I can't get the FM broadcast, the web broadcast, T&S ... anything while walking around the track.

Luckily the cars sound good.

That's very true- I did actually turn it off a few times during practice for that very reason- but it was frustrating to not have anything for the entire 12 hours.

[ATLFalconsFAN]

Originally Posted by fergus_r

I thought the Historics were a great addition and filled what would have been empty space very nicely. Great mix of cars and a decent number of them, with some good racing and some interesting lines through the hairpin!

You're more forgiving than me. I thought that historics field was garbage.

[FormulaFox]

Originally Posted by EffectiveSprinkles

I would say this is simply completely untrue. If only because you have no idea about the circumstances of that one outlier lap.

What you're ignoring is the fact that those laps, outlier or not, are still the most clear example of what the car is capable of. If the BoP isn't that close, the cars will NEVER be that close - not over one lap, not two, three or whatever.

The fastest laps the cars post are the biggest indicator of the car's maximum performance potential under the current BoP. Data over multiple laps is skewed by things like the varying skills of the car's drivers, how quickly the tires wear based on their setup, and even loss of engine power if an undetected problem starts to crop up.

IMSA has had to put a ton of measuring equipment on the cars to account for these variables. Since we don't have the data from that equipment we can't account for those variables, so the only trustworthy data we can look at is the proven ultimate speed of the cars - IE, their fastest lap over the race weekend.

You seem to want to argue the BoP was 'very close' but provide zero evidence and ignore evidence others present.

First of all, I have produced very clear evidence of what the cars showed themselves capable of at Sebring. Nothing you have provided refutes it.

Secondly, I never said the BoP is "very" close, I said it's closer than people want to admit. (as you're proving now)

[cbbrit]

Some post-race news:

http://www.racer.com/imsa/item/14819...-sebring-crash

[EffectiveSprinkles]

Originally Posted by FormulaFox

The fastest laps the cars post are the biggest indicator of the car's maximum performance potential under the current BoP.

I'm sorry to repeat myself but this is quite simply untrue. Once again, a single lap says nothing about a car's performance relative to other cars because you don't know the specific unique circumstances of that lap.

That is why you take averages. Then you filter out anomolies and get the bigger picture. I'm trying here but I struggle to find any reason why anyone would refute that other than ulterior motives. The data was presented by another member quite clearly.

Let alone the fact that BoP is by anyone's admission squarely focused on equalizing average performance and not single laps.