2017 LeMans
07-18-2017, 12:25 PM
#376
Being such a fan you'd likely be very interesting in what Race Car Engineering has to say on the subject (August issue). They are written largely for a professional audience, and have IMHO consistently the best technical analysis in the business.
This quote was interesting re luck on repairing the damaged #2 car:
Originally Posted by Race Car Engineering
"When we came in, we knew that the initial damage was caused by the front axle drivetrain failure", said team principle Andreas Seidl. "Since we couldn't switch on the hybrid system before replacing the entire front axle, we couldn't diagnose 100 percent if the inverter or battery also got damaged as a consequence. Therefore, we had to decide if we risk first to change the front axle only, and then switch on the hybrid system afterwards and check if all was fine. This is what we actually did, and it saved us the race win. If the battery was also damaged, we would have changed the entire front axle, and then we would have had to open up the car again a second time."
The gamble worked and the car then ran reliably to the end of the race.
The gamble worked and the car then ran reliably to the end of the race.
07-18-2017, 12:49 PM
#377
Drifting
And if they'd done the same at Le Mans I'd be impressed. But the data shows that was far from the case.
Being such a fan you'd likely be very interesting in what Race Car Engineering has to say on the subject (August issue). They are written largely for a professional audience, and have IMHO consistently the best technical analysis in the business.
This quote was interesting re luck on repairing the damaged #2 car:
Being such a fan you'd likely be very interesting in what Race Car Engineering has to say on the subject (August issue). They are written largely for a professional audience, and have IMHO consistently the best technical analysis in the business.
This quote was interesting re luck on repairing the damaged #2 car:
I interpret the quote as follows:
- Failure occurs ~4 hours into race (first LMP1H to hit serious trouble)
- Unsure if inverter / battery damaged
- Opportunity to change front axle ONLY and then check hybrid
- IF no damage to hybrid, car can rejoin race (but unknown)
- IF damage to hybrid, take panels off car, hybrid repair, car can rejoin
race (more time consuming than completing both repairs while car is
apart)
I think that's a calculated risk that any team would probably take given those circumstances; why not?
07-18-2017, 01:16 PM
#378
I read RCE from time to time, but not with any degree of regularity, as I'm a banker rather than an automotive engineer.
I interpret the quote as follows:
- Failure occurs ~4 hours into race (first LMP1H to hit serious trouble)
- Unsure if inverter / battery damaged
- Opportunity to change front axle ONLY and then check hybrid
- IF no damage to hybrid, car can rejoin race (but unknown)
- IF damage to hybrid, take panels off car, hybrid repair, car can rejoin
race (more time consuming than completing both repairs while car is
apart)
I think that's a calculated risk that any team would probably take given those circumstances; why not?
I interpret the quote as follows:
- Failure occurs ~4 hours into race (first LMP1H to hit serious trouble)
- Unsure if inverter / battery damaged
- Opportunity to change front axle ONLY and then check hybrid
- IF no damage to hybrid, car can rejoin race (but unknown)
- IF damage to hybrid, take panels off car, hybrid repair, car can rejoin
race (more time consuming than completing both repairs while car is
apart)
I think that's a calculated risk that any team would probably take given those circumstances; why not?
A) 1:05 stop with a risk of it becoming nearly 3:00.
B) ~2:00 stop guaranteed.
I think most would roll the dice, but that's what it was.
Toyota's design on the other hand didn't allow for option A). They had to take B) and lost in part because of it.
Some of the other analysis is worthwhile. Porsche "did not have the downforce to challenge the Toyota in wet or dry conditions", but they felt they closed the gap in hot conditions (and it was very hot during the day).
I'm not an automotive engineer either (just a regular one), but I find their post-race analysis articles are some of their most accessible.
07-18-2017, 01:49 PM
#379
Drifting
I think the options were probably something like:
A) 1:05 stop with a risk of it becoming nearly 3:00.
B) ~2:00 stop guaranteed.
I think most would roll the dice, but that's what it was.
Toyota's design on the other hand didn't allow for option A). They had to take B) and lost in part because of it.
Some of the other analysis is worthwhile. Porsche "did not have the downforce to challenge the Toyota in wet or dry conditions", but they felt they closed the gap in hot conditions (and it was very hot during the day).
I'm not an automotive engineer either (just a regular one), but I find their post-race analysis articles are some of their most accessible.
A) 1:05 stop with a risk of it becoming nearly 3:00.
B) ~2:00 stop guaranteed.
I think most would roll the dice, but that's what it was.
Toyota's design on the other hand didn't allow for option A). They had to take B) and lost in part because of it.
Some of the other analysis is worthwhile. Porsche "did not have the downforce to challenge the Toyota in wet or dry conditions", but they felt they closed the gap in hot conditions (and it was very hot during the day).
I'm not an automotive engineer either (just a regular one), but I find their post-race analysis articles are some of their most accessible.
Porsche - evidently - know what it takes to win at Le Mans, whereas Toyota either don't know or cannot execute effectively based on that knowledge.
Related - this from Toyota Gazoo today:
Following analysis of the bodywork on the #7 TS050 HYBRID after the 6 Hours of Nürburgring, TOYOTA GAZOO Racing has identified the specific issue which caused an unexpected change in aerodynamic performance during the race.
The pole-position-winning car had led the early stages but suffered a loss of performance in the middle of the race, which prevented it challenging the leading Porsches. During the race this was identified as an issue with aerodynamic balance migration.
Post-race investigation has revealed significant damage to the underfloor of the #7 car as well as a hole in the rear wing, which caused cracks in the main plane during the race. The team believes this damage was caused by kerb riding for the underfloor and by unidentified flying debris which struck the leading edge of the rear wing main plane.
The pole-position-winning car had led the early stages but suffered a loss of performance in the middle of the race, which prevented it challenging the leading Porsches. During the race this was identified as an issue with aerodynamic balance migration.
Post-race investigation has revealed significant damage to the underfloor of the #7 car as well as a hole in the rear wing, which caused cracks in the main plane during the race. The team believes this damage was caused by kerb riding for the underfloor and by unidentified flying debris which struck the leading edge of the rear wing main plane.
07-20-2017, 03:33 AM
#380
Rennlist Member
I think the options were probably something like:
A) 1:05 stop with a risk of it becoming nearly 3:00.
B) ~2:00 stop guaranteed.
I think most would roll the dice, but that's what it was.
Toyota's design on the other hand didn't allow for option A). They had to take B) and lost in part because of it.
Some of the other analysis is worthwhile. Porsche "did not have the downforce to challenge the Toyota in wet or dry conditions", but they felt they closed the gap in hot conditions (and it was very hot during the day).
I'm not an automotive engineer either (just a regular one), but I find their post-race analysis articles are some of their most accessible.
A) 1:05 stop with a risk of it becoming nearly 3:00.
B) ~2:00 stop guaranteed.
I think most would roll the dice, but that's what it was.
Toyota's design on the other hand didn't allow for option A). They had to take B) and lost in part because of it.
Some of the other analysis is worthwhile. Porsche "did not have the downforce to challenge the Toyota in wet or dry conditions", but they felt they closed the gap in hot conditions (and it was very hot during the day).
I'm not an automotive engineer either (just a regular one), but I find their post-race analysis articles are some of their most accessible.
Pete,
I wouldn't put too much trust on journalists getting everything right.
I had talked to Frank Walliser before the race about their chances of winning, he was confident despite the time difference in qualifying. He mentioned the reliability issue and how the 919 are packaged in such a way that they can change stuff 'on the fly' if something goes wrong, 'stuff' on the 919 are 'modules', as in modular.
After the race I didn't get a chance to talk to him again, but I saw him a week later at Goodwood and we chatted again, not about the GT2RS but about Le Mans. (I grilled Andreas on the GT2RS instead after). Anyway, he said they couldn't quite figure out what was wrong with the car, but they took out the whole 'module', that includes everything that they had suspected that had gone wrong, he said it was the same as changing a gear box, quicker and easier to switch out the whole thing than trying to open up and replace an individual gear that went wrong. Toyota's car wasn't a 'modular design, hence they had to get to the root of the problem and replace the specific part.
Timo also confirmed that with me later on separately. (He and I have a bunch of history)
This is the philosophical difference in design between the Porsche car and the Toyota car. Porsche designed their cars to be easily fixed, while Toyota designed theirs to be as light as possible as a sprinter, but if something happens they are in trouble. One reason why Toyotas are quicker at qualifying, but if something happens Porsches are quicker to be mended and get back to the race. Toyota cars are sprinters, Porsches are proper endurance racers.
07-20-2017, 05:43 AM
#381
^I get that. Porsche and Audi have a long history with that modular philosophy. Bentley's was closer to Toyota's when they won it a couple years ago. Which is superior becomes apparent on the day.
I must say I've been impressed with Toyota's efforts the last few years, particularly when they were giving Porsche a run despite a fraction of the operating budget. That said it's still clear who's the master and the apprentice when it comes to many of the nuances.
I must say I've been impressed with Toyota's efforts the last few years, particularly when they were giving Porsche a run despite a fraction of the operating budget. That said it's still clear who's the master and the apprentice when it comes to many of the nuances.
07-20-2017, 07:14 AM
#382
Pete,
I wouldn't put too much trust on journalists getting everything right.
I had talked to Frank Walliser before the race about their chances of winning, he was confident despite the time difference in qualifying. He mentioned the reliability issue and how the 919 are packaged in such a way that they can change stuff 'on the fly' if something goes wrong, 'stuff' on the 919 are 'modules', as in modular.
After the race I didn't get a chance to talk to him again, but I saw him a week later at Goodwood and we chatted again, not about the GT2RS but about Le Mans. (I grilled Andreas on the GT2RS instead after). Anyway, he said they couldn't quite figure out what was wrong with the car, but they took out the whole 'module', that includes everything that they had suspected that had gone wrong, he said it was the same as changing a gear box, quicker and easier to switch out the whole thing than trying to open up and replace an individual gear that went wrong. Toyota's car wasn't a 'modular design, hence they had to get to the root of the problem and replace the specific part.
Timo also confirmed that with me later on separately. (He and I have a bunch of history)
This is the philosophical difference in design between the Porsche car and the Toyota car. Porsche designed their cars to be easily fixed, while Toyota designed theirs to be as light as possible as a sprinter, but if something happens they are in trouble. One reason why Toyotas are quicker at qualifying, but if something happens Porsches are quicker to be mended and get back to the race. Toyota cars are sprinters, Porsches are proper endurance racers.
I wouldn't put too much trust on journalists getting everything right.
I had talked to Frank Walliser before the race about their chances of winning, he was confident despite the time difference in qualifying. He mentioned the reliability issue and how the 919 are packaged in such a way that they can change stuff 'on the fly' if something goes wrong, 'stuff' on the 919 are 'modules', as in modular.
After the race I didn't get a chance to talk to him again, but I saw him a week later at Goodwood and we chatted again, not about the GT2RS but about Le Mans. (I grilled Andreas on the GT2RS instead after). Anyway, he said they couldn't quite figure out what was wrong with the car, but they took out the whole 'module', that includes everything that they had suspected that had gone wrong, he said it was the same as changing a gear box, quicker and easier to switch out the whole thing than trying to open up and replace an individual gear that went wrong. Toyota's car wasn't a 'modular design, hence they had to get to the root of the problem and replace the specific part.
Timo also confirmed that with me later on separately. (He and I have a bunch of history)
This is the philosophical difference in design between the Porsche car and the Toyota car. Porsche designed their cars to be easily fixed, while Toyota designed theirs to be as light as possible as a sprinter, but if something happens they are in trouble. One reason why Toyotas are quicker at qualifying, but if something happens Porsches are quicker to be mended and get back to the race. Toyota cars are sprinters, Porsches are proper endurance racers.
07-20-2017, 09:03 AM
#383
Rennlist Member
07-20-2017, 10:06 AM
#384
There is no doubt the LMP1 win was a great team effort, nontheless luck played its part and Porsche were prepared for that eventuality.
The bigger problem for Porsche is the RSR - to put it simply it doesn't have the dynamic headroom and thats largely due to the engine. Wrong engine, right placement
. Currently, the RSR is like the P51 Mustang with the Allison engine - this aircraft was transformed by an engine transplant - RR Merlin.
The job for Porsche is simpler, they have the 4l engine. All they need to do is add two turbos - this plus the mid-engined balance and new aero will allow them to better trade off in BoP.
Last edited by randr; 07-20-2017 at 10:34 AM.
07-20-2017, 10:46 AM
#385
Originally Posted by Race Car Engineering
The dreaded Balance of Performance was as close to perfect as anyone could wish for, and there were an astonishing 52 changes of lead in the class; each of the five manufactures that started the race led at one stage or another. The No.91 Porsche was in contention for the race win, but dropped out of the battle with a puncture with one hour remaining...
What you seemingly fail to recognize is that if Porsche upgraded the engine in the RSR as you request the FIA would simply slow it down in equal measure. How much potential an engine has on paper is immaterial- many of these cars run far less hp in race trim than they have on the street in order to facilitate close racing.
If you want to get faster in GTE you do as Ford did and "lobby" to tip the BOP in your favor, simple as that...
Case in point: http://www.roadandtrack.com/motorspo...ts-at-le-mans/
07-20-2017, 12:13 PM
#386
Drifting
Totally agree, Toyota have done a remarkable job - the Porsche win was more of a case of "chance favours the prepared mind".
There is no doubt the LMP1 win was a great team effort, nontheless luck played its part and Porsche were prepared for that eventuality.
The bigger problem for Porsche is the RSR - to put it simply it doesn't have the dynamic headroom and thats largely due to the engine. Wrong engine, right placement.
Currently, the RSR is like the P51 Mustang with the Allison engine - this aircraft was transformed by an engine transplant - RR Merlin.
The job for Porsche is simpler, they have the 4l engine. All they need to do is add two turbos - this plus the mid-engined balance and new aero will allow them to better trade off in BoP.
There is no doubt the LMP1 win was a great team effort, nontheless luck played its part and Porsche were prepared for that eventuality.
The bigger problem for Porsche is the RSR - to put it simply it doesn't have the dynamic headroom and thats largely due to the engine. Wrong engine, right placement
. Currently, the RSR is like the P51 Mustang with the Allison engine - this aircraft was transformed by an engine transplant - RR Merlin.
The job for Porsche is simpler, they have the 4l engine. All they need to do is add two turbos - this plus the mid-engined balance and new aero will allow them to better trade off in BoP.
To me this indicates a lack of understanding of the "Balance of Performance" rules. Race car engineering's take on GTE:
In other words there's nothing to complain about.
What you seemingly fail to recognize is that if Porsche upgraded the engine in the RSR as you request the FIA would simply slow it down in equal measure. How much potential an engine has on paper is immaterial- many of these cars run far less hp in race trim than they have on the street in order to facilitate close racing.
If you want to get faster in GTE you do as Ford did and "lobby" to tip the BOP in your favor, simple as that...
Case in point: http://www.roadandtrack.com/motorspo...ts-at-le-mans/
In other words there's nothing to complain about.
What you seemingly fail to recognize is that if Porsche upgraded the engine in the RSR as you request the FIA would simply slow it down in equal measure. How much potential an engine has on paper is immaterial- many of these cars run far less hp in race trim than they have on the street in order to facilitate close racing.
If you want to get faster in GTE you do as Ford did and "lobby" to tip the BOP in your favor, simple as that...
Case in point: http://www.roadandtrack.com/motorspo...ts-at-le-mans/
I expect they will be strong and have the pace to win at Lime Rock this weekend; less so at Road America.
07-20-2017, 05:08 PM
#387
To me this indicates a lack of understanding of the "Balance of Performance" rules. Race car engineering's take on GTE:
In other words there's nothing to complain about.
What you seemingly fail to recognize is that if Porsche upgraded the engine in the RSR as you request the FIA would simply slow it down in equal measure. How much potential an engine has on paper is immaterial- many of these cars run far less hp in race trim than they have on the street in order to facilitate close racing.
If you want to get faster in GTE you do as Ford did and "lobby" to tip the BOP in your favor, simple as that...
Case in point: http://www.roadandtrack.com/motorspo...ts-at-le-mans/
In other words there's nothing to complain about.
What you seemingly fail to recognize is that if Porsche upgraded the engine in the RSR as you request the FIA would simply slow it down in equal measure. How much potential an engine has on paper is immaterial- many of these cars run far less hp in race trim than they have on the street in order to facilitate close racing.
If you want to get faster in GTE you do as Ford did and "lobby" to tip the BOP in your favor, simple as that...
Case in point: http://www.roadandtrack.com/motorspo...ts-at-le-mans/
Remains to be seen how well the analysis is with torque curves. Also, the other issue is the differences between the FIA theoretical lap time data and actual race performance. Torque tends to win races over momentum cars. Tend to agree with Randr.
07-20-2017, 05:11 PM
#388
Torque is the main problem with the RSR and it will continue to be as long as it stays NA. The BOP is skewed towards cars with high torque and in some ways turbos over NA. Aston lobbied as this may be there last year so that was an outlier.
07-20-2017, 05:40 PM
#389
Drifting
They ought to be strong at LRP and Laguna in particular on the upcoming schedule.
I'm planning on being at the rest of the IMSA season after this weekend, which I am skipping.
07-20-2017, 07:59 PM
#390
That is not the correct understanding of BOP either! The FIA now uses an algorithm to analyze data to eliminate the "lobbying." ACO uses its own data for Le Mans. All adjustments are based on data analysis. The data sets have been agreed upon by the OEMs.
Remains to be seen how well the analysis is with torque curves. Also, the other issue is the differences between the FIA theoretical lap time data and actual race performance. Torque tends to win races over momentum cars. Tend to agree with Randr.
Remains to be seen how well the analysis is with torque curves. Also, the other issue is the differences between the FIA theoretical lap time data and actual race performance. Torque tends to win races over momentum cars. Tend to agree with Randr.
Remember that turbocharging has detractors other than lag, such as increased requirement for heat dissipation, exhaust wheel attrition (over a 24 hr race), packaging.