Laguna Seca: low-grip surface?
09-11-2018, 12:58 PM
#31
I won't .beat up on Mark- I met him at Laguna Seca and spoke a few times- he was a good guy.
Our experience with both cars is after racing on the East Coast and midwest for many years, we moved everything out West and promptly had to add front end downforce- both diveplanes and suspension adjustments.
Cars pushed not just at LS but Sear's Point as well.
Our experience with both cars is after racing on the East Coast and midwest for many years, we moved everything out West and promptly had to add front end downforce- both diveplanes and suspension adjustments.
Cars pushed not just at LS but Sear's Point as well.
09-11-2018, 03:05 PM
#33
Rennlist Member
I won't .beat up on Mark- I met him at Laguna Seca and spoke a few times- he was a good guy.
Our experience with both cars is after racing on the East Coast and midwest for many years, we moved everything out West and promptly had to add front end downforce- both diveplanes and suspension adjustments.
Cars pushed not just at LS but Sear's Point as well.
Our experience with both cars is after racing on the East Coast and midwest for many years, we moved everything out West and promptly had to add front end downforce- both diveplanes and suspension adjustments.
Cars pushed not just at LS but Sear's Point as well.
Mark I think you are a smart guy and add to the conversation. Others may disagree but I find you entertaining. But every once in a while, like this thread, I feel like you stake out a position that is so far out there that I wonder if you are trolling everyone and just giggling to yourself.
Banked corners are a different challenge all together. You can have a slippery surface, but with enough banking still carry high speeds and have high g's
The hairpin at Chuckwalla definitely has more "grip" due to it's banking than those turns you listed. Personally, I don't think banked corners are a fair test of grip since there are other physics involved; nor are they as much fun in my opinion.
The hairpin at Chuckwalla definitely has more "grip" due to it's banking than those turns you listed. Personally, I don't think banked corners are a fair test of grip since there are other physics involved; nor are they as much fun in my opinion.
So the Pro drivers this weekend at the IMSA aren't skilled? They commented during their interviews that Laguna is more slick and has less grip than other tracks that they race in the IMSA series.
It sounds like you have been taking this as a personal attack from the beginning of the thread. Your defense of Laguna's reputation goes against the opinion of every racer who has been to multiple tracks.
Low grip isn't a bad thing, it is just an observation and it is an equal handicap for all cars.
It sounds like you have been taking this as a personal attack from the beginning of the thread. Your defense of Laguna's reputation goes against the opinion of every racer who has been to multiple tracks.
Low grip isn't a bad thing, it is just an observation and it is an equal handicap for all cars.
Yes, your first posit is true. But these drivers have a better calibrated *** than even you, and they're counting on grip that isn't there. Hence, the track surface is lower grip than other tracks they go to. Period.
Most tracks have high speed straights and low speed turns. Laguna Seca is lower in top speed than almost all the big East Coast and Midwest tracks, it also has the slowest corner of any of the major tracks including Namerow at Mont Tremblant and Turn 7 at Sebring. It's not that quick a track, top or bottom. Turn 3, 4, 6, 8, 9, 10 are NOT 90 degree turns. Turns 2, 5, 6, 8A, 9 and 10 are well cambered (banked).
Umm, no. While there is good grip, relative to the other turns, at Turns 5, 6 and 10, the cornering g's are NOT higher here than most ANY other turns in racing.
Mark, you need to get out more...
Most tracks have high speed straights and low speed turns. Laguna Seca is lower in top speed than almost all the big East Coast and Midwest tracks, it also has the slowest corner of any of the major tracks including Namerow at Mont Tremblant and Turn 7 at Sebring. It's not that quick a track, top or bottom. Turn 3, 4, 6, 8, 9, 10 are NOT 90 degree turns. Turns 2, 5, 6, 8A, 9 and 10 are well cambered (banked).
Umm, no. While there is good grip, relative to the other turns, at Turns 5, 6 and 10, the cornering g's are NOT higher here than most ANY other turns in racing.
Mark, you need to get out more...
now you say that turn 3, 4,(never said 6), 8, 9 and 10 are not 90 degree turns? turn 2 is not well cambered . and yes, the cambered turns of turn 5 and 10 are very high grip and have the highest g loadings of most turns around.. check the data. I dont know what kind of grades YOU got in Geometry, but mine were quite good.
the turns i said were 90s are close enough for our discussions. (see map below). COMPARE Sonoma and laguna. what totally different configurations and flows.... im sure , with all your track experience you understand flow of a track and how drivers push in certain areas to create grip issues.bottom line. Im ONLY saying that most people always tend to blame a track for car or control issues. laguna is unique and because it is not as fast as many other tracks, and drivers want to go fast, they overcook many of the turns. because the turns are NOT cambered and cut back a little with little reference, people over driver and go off track a lot. you dont see this at many other tracks because of the configuration
Sonoma raceway is simlar in speed and grip, but the turns are totally different.
now, if you have peak g loading data for other tracks and their turns that are not on cambered tuns showing higher values, then i would stand corrected. i think that data will be hard to find.
09-11-2018, 03:13 PM
#34
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While debris on the surface is always a possibility, one not limited to WLSR, the “low grip” condition relative to other tracks is not dynamic or variable.
Also, unlike some other well-worn, “seasoned” tracks that start quick in the morning and slow through the day with temperature increases (a degradation which can be logged and counted on, for set up purposes), WLSR is significant in the fact that it starts out slippery and never really improves with rubber down.
The reason why this occurs is because the chemical reaction that occurs between “rubbered in” tracks and “green” tracks that leveraged the grip between the Tire tread and the track surface never seems to occur.
The aggregate and binder chemicals on this track are so smooth and polished, that there’s no transfer of rubber to the asphalt surface to begin building this sticky, grippy interface between the tire and the track.
And heaven forbid the fog rolls in in the evening carrying through the morning. Moisture on top of glass is what some people refer to the feeling they have!
The best attribute of a top-level driver is maximum seat time in a variety of different cars on different tires. With that experience, those drivers come to rely on a particular and relatively narrow window of capable behavior.
The fact that more than a few are miscalculating and edging over WHAT they THINK they SHOULD have in terms of grip, particularly when they “send it,” is indicative of the TRACK being the outlier, not the drivers, cars or tires.
Camber gain is not in the equation, because you can add that to the equation of expected benefit.
A great technical exercise as a driver, for sure!
Also, unlike some other well-worn, “seasoned” tracks that start quick in the morning and slow through the day with temperature increases (a degradation which can be logged and counted on, for set up purposes), WLSR is significant in the fact that it starts out slippery and never really improves with rubber down.
The reason why this occurs is because the chemical reaction that occurs between “rubbered in” tracks and “green” tracks that leveraged the grip between the Tire tread and the track surface never seems to occur.
The aggregate and binder chemicals on this track are so smooth and polished, that there’s no transfer of rubber to the asphalt surface to begin building this sticky, grippy interface between the tire and the track.
And heaven forbid the fog rolls in in the evening carrying through the morning. Moisture on top of glass is what some people refer to the feeling they have!
The best attribute of a top-level driver is maximum seat time in a variety of different cars on different tires. With that experience, those drivers come to rely on a particular and relatively narrow window of capable behavior.
The fact that more than a few are miscalculating and edging over WHAT they THINK they SHOULD have in terms of grip, particularly when they “send it,” is indicative of the TRACK being the outlier, not the drivers, cars or tires.
Camber gain is not in the equation, because you can add that to the equation of expected benefit.
A great technical exercise as a driver, for sure!
09-12-2018, 04:03 AM
#35
Rennlist Member
While debris on the surface is always a possibility, one not limited to WLSR, the “low grip” condition relative to other tracks is not dynamic or variable.
Also, unlike some other well-worn, “seasoned” tracks that start quick in the morning and slow through the day with temperature increases (a degradation which can be logged and counted on, for set up purposes), WLSR is significant in the fact that it starts out slippery and never really improves with rubber down.
The reason why this occurs is because the chemical reaction that occurs between “rubbered in” tracks and “green” tracks that leveraged the grip between the Tire tread and the track surface never seems to occur.
The aggregate and binder chemicals on this track are so smooth and polished, that there’s no transfer of rubber to the asphalt surface to begin building this sticky, grippy interface between the tire and the track.
And heaven forbid the fog rolls in in the evening carrying through the morning. Moisture on top of glass is what some people refer to the feeling they have!
The best attribute of a top-level driver is maximum seat time in a variety of different cars on different tires. With that experience, those drivers come to rely on a particular and relatively narrow window of capable behavior.
The fact that more than a few are miscalculating and edging over WHAT they THINK they SHOULD have in terms of grip, particularly when they “send it,” is indicative of the TRACK being the outlier, not the drivers, cars or tires.
Camber gain is not in the equation, because you can add that to the equation of expected benefit.
A great technical exercise as a driver, for sure!
Also, unlike some other well-worn, “seasoned” tracks that start quick in the morning and slow through the day with temperature increases (a degradation which can be logged and counted on, for set up purposes), WLSR is significant in the fact that it starts out slippery and never really improves with rubber down.
The reason why this occurs is because the chemical reaction that occurs between “rubbered in” tracks and “green” tracks that leveraged the grip between the Tire tread and the track surface never seems to occur.
The aggregate and binder chemicals on this track are so smooth and polished, that there’s no transfer of rubber to the asphalt surface to begin building this sticky, grippy interface between the tire and the track.
And heaven forbid the fog rolls in in the evening carrying through the morning. Moisture on top of glass is what some people refer to the feeling they have!
The best attribute of a top-level driver is maximum seat time in a variety of different cars on different tires. With that experience, those drivers come to rely on a particular and relatively narrow window of capable behavior.
The fact that more than a few are miscalculating and edging over WHAT they THINK they SHOULD have in terms of grip, particularly when they “send it,” is indicative of the TRACK being the outlier, not the drivers, cars or tires.
Camber gain is not in the equation, because you can add that to the equation of expected benefit.
A great technical exercise as a driver, for sure!
again, all you need to see is the data. that will tell you if the track is slick or not compared to others. there is SO much grip on the exit of turn 11.. the announcers (not tommy kendall that cant do anything wrong in my mind) said "astroturf" they also said the track was "slick" they are clueless . the green surface is HIGH grip. (its NOT astro turf, though it was a few years ago) i would over bake turn 11 in my last race last month, and when it slide out to the green area, it would hook up like i was on michellin slicks! super high grip area off the rubble strip . i usuall had one set of tires on the green and strattled the exit birm. (red and white ). im just saying. the announcers just say things that they think they know.. then, you have 5, 6, 8, 9, 10 and again 11 , all super high grip turns due to banking camber...... more than half the turns of the track are VERY high grip.
09-12-2018, 04:09 AM
#36
Rennlist Member
09-12-2018, 09:49 AM
#37
WRLS
The grip out there this past weekend was low in my opinion. My coach has been racing cars and motorcycles at LS for twenty years and he told me “careful, the track has a low grip surface” when I went out on my first session this past weekend. If Mike Hedlund, Peter, and my coach are saying that LS has a low grip surface, I’m guessing they probably are correct. I certainly felt it had less grip than Buttonwillow had the weekend prior.
09-12-2018, 09:59 AM
#38
Three Wheelin'
Lateral acceleration measurements aren't the whole story. It requires a 3 axis accelerometer and some math (not difficult math) to normalize the Ay signal to account for the banking. If you do that you can get the mu value of the asphalt. I think what others are trying to say here is that the mu value of the track surface is lower than other tracks. That's what the data I have says. The elevation and camber definitely help increase the lateral acceleration, but for an equivalent surface you'd likely still find that the acceleration numbers could be higher given a better surface.
09-12-2018, 11:52 AM
#39
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Lateral acceleration measurements aren't the whole story. It requires a 3 axis accelerometer and some math (not difficult math) to normalize the Ay signal to account for the banking. If you do that you can get the mu value of the asphalt. I think what others are trying to say here is that the mu value of the track surface is lower than other tracks. That's what the data I have says. The elevation and camber definitely help increase the lateral acceleration, but for an equivalent surface you'd likely still find that the acceleration numbers could be higher given a better surface.
09-12-2018, 01:34 PM
#40
Rennlist Member
Not really... its feeling vs facts here
That is my point. its "feelings" for the most part, and who cares if thre is banking on several of the turns. when i go, i feel that those turns have great grip... those turns are part of the track, right, so where is the feeling of low grip felt? lets talk about turn 3, 4, and maybe9 or 11. (remember, 11 now has trendous grip as you exit)... so what data do you have on the turns that dont have banking vs other turns that dont as well at other tracks. in the state, in the country, what are you comparing it too?? personally, i dont think the surface has any less grip than Sonoma, buttonwillow, willow springs, thunderhilll, or cal speedway. I just dont see it. infact, there has been more variability due to conditions, than the surface creates. and again, that's with more race days at the track than most.
What does your data say? what data are you looking at? I know this is a silly argumet, but its a racing discussion so its interesting. i hear a lot of people talk about surface conditions to explain why they are running off the pace. thats just it. many times its feelings, many times its an excuse. and sometimes the surface is actually the issue. but to say lagunas surface has less grip overall vs other tracks is a claim that generally has little basis based on shear number of variables. again with most of th turns having more banking than other tracks, wouldn't that show data of higher lateral accelerations? we are talking more than half the track here. then, couple that with the seemingly, and comparitively awkeward turn approaches , which provide challenges for drivers to put the car in the right balance position. this can cause the car to be unsettled , ONLY because of the errors in overdriving those turns in speed, position and timing. IF you are ignoring those factors, i feel you might be ignoring major components of what a track "feels " like.
example.. personally, i think sonoma has terrible grip.. but I know thats ONLY because my car and tire set up vs my competiors is not as ideal (set up, weight, tire quality, etc) which is less of a factor at Laguna (for me)
cars need to be set up for particular tracks and Laguna is no different than other tracks in that regard. Poor set up can feel like the track has less grip than others if not set up optimally, even if the surface is the same quality. do you not agree?
Mk
what kind of lap times were you running at laguna vs buttonwillow (config ?) its the job of the coach to make you aware of the tracks characteristics. yes, the track can ack like it has less grip, when actually it might not be the case. again, the reasn you have to be careful at laguna is not so much the grip levels, but the position the car gets in before turns, that comprimises grip. the net message is the same, the cause is the only difference. the only way to know is with data and feel. Im have certain things i key on , like throttle position, power level and stering input which most people dont pay attention too. iI know i have grip ,when i can be at near redline, 3rd gear, 110mph, and have a known level of steering input at WOT....... so tracks , or particular days or tires, will give me massive movement, and others, complete confidence. this is the type of feelings im set up to use and coach with as well. Others might just report how the car is dancing around , and that can be purely dependent on many other factors.. i try and rule out those factors. another example is a straight liine, redline shift. do i get wheel spin or not? these kinds of things can show you the grip you have available. usually, its due to other factors OTHER than the track surface
Lateral acceleration measurements aren't the whole story. It requires a 3 axis accelerometer and some math (not difficult math) to normalize the Ay signal to account for the banking. If you do that you can get the mu value of the asphalt. I think what others are trying to say here is that the mu value of the track surface is lower than other tracks. That's what the data I have says. The elevation and camber definitely help increase the lateral acceleration, but for an equivalent surface you'd likely still find that the acceleration numbers could be higher given a better surface.
What does your data say? what data are you looking at? I know this is a silly argumet, but its a racing discussion so its interesting. i hear a lot of people talk about surface conditions to explain why they are running off the pace. thats just it. many times its feelings, many times its an excuse. and sometimes the surface is actually the issue. but to say lagunas surface has less grip overall vs other tracks is a claim that generally has little basis based on shear number of variables. again with most of th turns having more banking than other tracks, wouldn't that show data of higher lateral accelerations? we are talking more than half the track here. then, couple that with the seemingly, and comparitively awkeward turn approaches , which provide challenges for drivers to put the car in the right balance position. this can cause the car to be unsettled , ONLY because of the errors in overdriving those turns in speed, position and timing. IF you are ignoring those factors, i feel you might be ignoring major components of what a track "feels " like.
example.. personally, i think sonoma has terrible grip.. but I know thats ONLY because my car and tire set up vs my competiors is not as ideal (set up, weight, tire quality, etc) which is less of a factor at Laguna (for me)
cars need to be set up for particular tracks and Laguna is no different than other tracks in that regard. Poor set up can feel like the track has less grip than others if not set up optimally, even if the surface is the same quality. do you not agree?
Mk
The grip out there this past weekend was low in my opinion. My coach has been racing cars and motorcycles at LS for twenty years and he told me “careful, the track has a low grip surface” when I went out on my first session this past weekend. If Mike Hedlund, Peter, and my coach are saying that LS has a low grip surface, I’m guessing they probably are correct. I certainly felt it had less grip than Buttonwillow had the weekend prior.
09-12-2018, 01:57 PM
#41
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09-12-2018, 04:52 PM
#43
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09-13-2018, 01:37 AM
#45
Mark thinks that we are somehow beating up on his favorite track by saying the surface is "low grip". I, by the way, concur that it is low grip. The first time a I rode there on a 1000cc super bike with 16.5 slicks taught me that. I had to be way more careful with throttle when leaned over compared to Thunderhill and Sears Point. But hey, we must all be wrong, right?