Finding max speed. How you know the limit without crashing ?
04-29-2018, 06:48 PM
#16
Again, in my car, I see The Esses as pretty much a big straight, except in the rain
Gary
04-29-2018, 07:08 PM
#17
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04-29-2018, 07:17 PM
#18
04-29-2018, 07:46 PM
#19
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I watched some on professionals' videos with data overlay, one was Graham Rahal, those drivers, are insane .
I don't think they hardly ever use their brakes from turn 1 to the bus stop.
04-29-2018, 07:57 PM
#21
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One of the great benefits of pro level sports racers (IMSA) and formula cars (IRL) is very effective aero for the weight of the car. On another level than the simple stick on wings and splitters for 3000+ lb cars on treaded tires, for sure!
04-29-2018, 08:10 PM
#22
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We can, with simple tools and no sensors, measure the forces acting on the car from all directions.
For this we would look at longitudinal g’s (Acceleration/Braking) and lateral g’s (Cornering).
We know that a car on street tires can generate long g (braking forces) at least 90% of the sustained lat g (cornering forces), cars on R-comps closer to 95% and slicks (real ones, DH/Michelin/Hoosier R80 or R100) between 95% and 100% of the cornering forces.
By using the friction circle measure (gSum), you can see your maximum sustained braking g and then you can see your maximum sustained cornering g. Don’t care what the numbers are, care what the proportional relationship is.
First question is whether the sustained braking g’s ARE in fact at least 90% of sustained cornering g’s. If not, why not?
Second question is how much of a drop in gSum is there between the end of braking and lat g at the apex?
Don’t tell me you don’t have a drop! Everyone has some, most have a longer and greater drop in that critical area between the end of slowing and the assumption of maximum cornering forces.
It’s also a good measure of how well you blend braking into the cornering phase (which is not necessarily trail-braking, a conscious, deliberate manipulation of the car’s weight distribution on the tires).
Every driver’s challenge is to master individual (axis) disciplines, then meld them together. More soon.
If you crash, you made way too big a jump. In something... Top level drivers nearly crash a thousand times a lap, but you can’t even see it, because the increments are SO fine and small between fast and too fast...
04-29-2018, 11:31 PM
#23
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Some great posts here and a good description by Peter.
I would add, that as you get better and better, you are able to refine the increments that you step up your performance. The goal is to make a mistake at 101% of the limit (car, tire, and driver) because that small mistake is one that we can recover from. When you make the 110% mistake, it's much harder to recover. 150% mistake and it's a spin or worse. That is why a seasoned pro or great amateur is able to drive at such a high level - they are able to correct all those little mistakes and make the whole thing seem near perfect, while to them it's a series of mistakes and corrections.
There are ways to look at this in data, but the real answer is experience, methodical,and deliberate practice, and careful risk assumption.
I would add, that as you get better and better, you are able to refine the increments that you step up your performance. The goal is to make a mistake at 101% of the limit (car, tire, and driver) because that small mistake is one that we can recover from. When you make the 110% mistake, it's much harder to recover. 150% mistake and it's a spin or worse. That is why a seasoned pro or great amateur is able to drive at such a high level - they are able to correct all those little mistakes and make the whole thing seem near perfect, while to them it's a series of mistakes and corrections.
There are ways to look at this in data, but the real answer is experience, methodical,and deliberate practice, and careful risk assumption.
04-30-2018, 08:19 AM
#24
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The goal is to make a mistake at 101% of the limit (car, tire, and driver) because that small mistake is one that we can recover from.
When you make the 110% mistake, it's much harder to recover.
150% mistake and it's a spin or worse.
That is why a seasoned pro or great amateur is able to drive at such a high level - they are able to correct all those little mistakes and make the whole thing seem near perfect, while to them it's a series of mistakes and corrections.
There are ways to look at this in data, but the real answer is experience, methodical,and deliberate practice, and careful risk assumption.
When you make the 110% mistake, it's much harder to recover.
150% mistake and it's a spin or worse.
That is why a seasoned pro or great amateur is able to drive at such a high level - they are able to correct all those little mistakes and make the whole thing seem near perfect, while to them it's a series of mistakes and corrections.
There are ways to look at this in data, but the real answer is experience, methodical,and deliberate practice, and careful risk assumption.
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-Peter Krause
www.peterkrause.net
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Consultation Available Remotely and at VIRginia International Raceway
04-30-2018, 10:25 AM
#26
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I have been to NJMP Lightning.
Beautiful track.
There is a lot of run off for sure, (one of the reasons I went there)
The day I was there, it seemed like the wrecker was going out every other session with cars running off.
That track is the only place (so far) that my car got squirrelly.
It was the turn with the uphill/down hill.
I did not hit the entry at the correct angle and when I crested the hill, the rear tires kicked out and car got loose to the left.
I corrected and accelerated to help straighten the car. It never went off, close enough for me.
BTW, there are a lot of tire marks on that corner.
04-30-2018, 10:29 AM
#27
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This is where the topography, the elevation changes that help or hurt the ability of the tires to stay in contact with the road, really comes into play. I assume you’re talking about Lightning T5? Also applies to T1.
Careful study and having the car point in the directions you want to go BEFORE you crest and get light is what you want to do to avoid this.
Careful study and having the car point in the directions you want to go BEFORE you crest and get light is what you want to do to avoid this.
04-30-2018, 10:51 AM
#28
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This is where the topography, the elevation changes that help or hurt the ability of the tires to stay in contact with the road, really comes into play. I assume you’re talking about Lightning T5? Also applies to T1.
Careful study and having the car point in the directions you want to go BEFORE you crest and get light is what you want to do to avoid this.
Careful study and having the car point in the directions you want to go BEFORE you crest and get light is what you want to do to avoid this.
It looks similar to the uphill at Lime Rock, which I hope to try soon
04-30-2018, 10:52 AM
#29
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04-30-2018, 03:43 PM
#30
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I have not done Thunderbolt yet.
I have been to NJMP Lightning.
That track is the only place (so far) that my car got squirrelly.
It was the turn with the uphill/down hill.
I did not hit the entry at the correct angle and when I crested the hill, the rear tires kicked out and car got loose to the left.
I corrected and accelerated to help straighten the car. It never went off, close enough for me.
BTW, there are a lot of tire marks on that corner.
I have been to NJMP Lightning.
That track is the only place (so far) that my car got squirrelly.
It was the turn with the uphill/down hill.
I did not hit the entry at the correct angle and when I crested the hill, the rear tires kicked out and car got loose to the left.
I corrected and accelerated to help straighten the car. It never went off, close enough for me.
BTW, there are a lot of tire marks on that corner.
I’ll be interested to hear your thoughts on how they compare once you’ve run TBolt.
Last edited by Nizer; 04-30-2018 at 04:11 PM.