[///M Power-Belgium]

Originally Posted by ///WORK-F36

+ 1 to that

Probably she will do it ..

[MrPrena]

Originally Posted by ///M Power-Belgium

It was actually the speed of boldness...daring , even when we can do it at topspeed first we/I need "big balls" to do it .
The problem is...Where is the limit ?
And when we find the limit at high speed ...It's probably too late , and game over !
So no extreme risks for me , but only calculated risks .
In other words it was fast...really fast but not too fast , and the concentration to do it is actually huge that's why I have also huge respect for top pilots .

Take also a look at this => http://www.m3post.com/forums/showthread.php?t=1177162

Eau Rouge is one area you need to "calculate" with physics to know your and car's limit. I agree.

Most of non-car freaks think lateral acceleration limit @r=x ft is the limit of the lateral "a", but that is just at that radius.

I think our E9x M3 can do about 1.1g at Eau Rouge. Meaning you gotta calculate accordingly, because you gotta go to the other side of the curve, and being 2.2g (hypothetical #) NET lat "a." (you can use a=v^2/r as a start, but real calculation can be severely more complicated).

As being said, with a car with mechanical grip street stock car without significant >g down force cannot go nearly as fast.
Need at least

Lateral A >3.8g to corner like GP2 or F1 cars.

Here are example.

2005 M. Schumacher 309km/hr at Eau Rouge exit with grooved tires.

2013 Alonso ~295km/h at Eau Rouge exit w/ slick soft

Ferrari 458 Speciale at Eau Rouge. Um, 120km/h? Lots of braking and downshifting on entry.

Speed Comparison: GT vs. F1 @ Eau Rouge

[Biorin]

Originally Posted by MrPrena

Most of non-car freaks think lateral acceleration limit @r=x ft is the limit of the lateral "a", but that is just at that radius.

I think our E9x M3 can do about 1.1g at Eau Rouge. Meaning you gotta calculate accordingly, because you gotta go to the other side of the curve, and being 2.2g (hypothetical #) NET lat "a." (you can use a=v^2/r as a start, but real calculation can be severely more complicated).

As being said, with a car with mechanical grip street stock car without significant >g down force cannot go nearly as fast.
Need at least

Lateral A >3.8g to corner like GP2 or F1 cars.

...

I have finally fixed this post. I think.

[///M Power-Belgium]

Originally Posted by MrPrena

Eau Rouge is one area you need to "calculate" with physics to know your and car's limit. I agree.

Most of non-car freaks think lateral acceleration limit @r=x ft is the limit of the lateral "a", but that is just at that radius.

I think our E9x M3 can do about 1.1g at Eau Rouge. Meaning you gotta calculate accordingly, because you gotta go to the other side of the curve, and being 2.2g (hypothetical #) NET lat "a." (you can use a=v^2/r as a start, but real calculation can be severely more complicated).

As being said, with a car with mechanical grip street stock car without significant >g down force cannot go nearly as fast.
Need at least

Lateral A >3.8g to corner like GP2 or F1 cars.

Here are example.

2005 M. Schumacher 309km/hr at Eau Rouge exit with grooved tires.



2013 Alonso ~295km/h at Eau Rouge exit w/ slick soft


Ferrari 458 Speciale at Eau Rouge. Um, 120km/h? Lots of braking and downshifting on entry.


Speed Comparison: GT vs. F1 @ Eau Rouge

Yep I see what you are talking about ..
Long story in short..
Few years back I drove on a road that I know really well , and only about 10-12 miles from my location .
It's about a slight straight downhill with a turn in the bottem to the right and then straight uphill , at first I was really scared to take this turn at high speed .
Now I'm used to take this turn at high speed , but the first time that I took it really fast it actually scared the shit out of me..
The reason why was that I felt that the downforce kicked in , it's a really strange and unexpected feeling and felt almost like someone pushed the car down on the road in a fraction of 1/10 seconde .
We normal people are never prepared to that downforce feeling and Eau Rouge at high speed ...at least when we have the balls it gets you that downforce feeling too .
When I want scare the shit of someone on my passenger seat I let them feel the feeling of downforce kicking ...
I never felt it before in my previous cars , but in my ///M3 I can feel it what means that the ..design , spoilers ect..of our cars really work to get serious downforce and they are not there only for the show .

[MrPrena]

Originally Posted by ///M Power-Belgium

Yep I see what you are talking about ..
Long story in short..
Few years back I drove on a road that I know really well , and only about 10-12 miles from my location .
It's about a slight straight downhill with a turn in the bottem to the right and then straight uphill , at first I was really scared to take this turn at high speed .
Now I'm used to take this turn at high speed , but the first time that I took it really fast it actually scared the shit out of me..
The reason why was that I felt that the downforce kicked in , it's a really strange and unexpected feeling and felt almost like someone pushed the car down on the road in a fraction of 1/10 seconde .
We normal people are never prepared to that downforce feeling and Eau Rouge at high speed ...at least when we have the balls it gets you that downforce feeling too .
When I want scare the shit of someone on my passenger seat I let them feel the feeling of downforce kicking ...
I never felt it before in my previous cars , but in my ///M3 I can feel it what means that the ..design , spoilers ect..of our cars really work to get serious downforce and they are not there only for the show .

If we have a real gt wing, we might get a downforce of .20-.35g at 150mph.
1.1g mechanical grip+ .25g aerodynamically grip is not bad.

[MrPrena]

ASBSECU E93 I got fumed by VW Jetta TDi Ultra High Sulfuric Diesel (UHSD) while driving E93 top down.

Last 5 sec with fume of exhaust coming out...

[ASBSECU E93]

Originally Posted by MrPrena

ASBSECU E93 I got fumed by VW Jetta TDi Ultra High Sulfuric Diesel (UHSD) while driving E93 top down.

Last 5 sec with fume of exhaust coming out...

Ha Ha!! That is the prior gen body style (MKVI) - and would have been the PD engine. 2009 and newer have the CR, or 'clean' diesel

Mine will blow a small plume of you put the hammer down....but that one wasn't even under much load to cause that smoke..?

[MrPrena]

Originally Posted by ASBSECU E93

Ha Ha!! That is the prior gen body style (MKVI) - and would have been the PD engine. 2009 and newer have the CR, or 'clean' diesel

Mine will blow a small plume of you put the hammer down....but that one wasn't even under much load to cause that smoke..?

Yeah. My wife leased a 2006 Jetta once. She really likes it. She said it almost feels like W204.
Funny it happened yesterday, and got the video of it.

[V1.47fan]

Originally Posted by MrPrena

Eau Rouge is one area you need to "calculate" with physics to know your and car's limit. I agree.

Most of non-car freaks think lateral acceleration limit @r=x ft is the limit of the lateral "a", but that is just at that radius.

I think our E9x M3 can do about 1.1g at Eau Rouge. Meaning you gotta calculate accordingly, because you gotta go to the other side of the curve, and being 2.2g (hypothetical #) NET lat "a." (you can use a=v^2/r as a start, but real calculation can be severely more complicated).

As being said, with a car with mechanical grip street stock car without significant >g down force cannot go nearly as fast.
Need at least

Lateral A >3.8g to corner like GP2 or F1 cars.

Here are example.

2005 M. Schumacher 309km/hr at Eau Rouge exit with grooved tires.

2013 Alonso ~295km/h at Eau Rouge exit w/ slick soft

Ferrari 458 Speciale at Eau Rouge. Um, 120km/h? Lots of braking and downshifting on entry.

Speed Comparison: GT vs. F1 @ Eau Rouge

Race car drivers dont actually calculate the limits when racing, there are so many variables. Determining braking points , entry/exit speed etc. Is more art than science, based on feel of what the car is doing...

[upstatedoc]

Enjoying a nice Cohiba extra vigoroso.

[MrPrena]

Originally Posted by V1.47fan

Race car drivers dont actually calculate the limits when racing, there are so many variables. Determining braking points , entry/exit speed etc. Is more art than science, based on feel of what the car is doing...

That is what telemetry softwares are for, but driver do need to go through what it needed to be done.
Yes, depends on type of tires, tire life, front and rear downforce, and 10^2 OTHER variables.

Sounds like you drove an 1.6-2.0L Formula classes in the past?

[C5driver]

Originally Posted by ///WORK-F36

+ 1 to that

[Axius]

So...., I found a bike that I want for my collection;

[UncleWede]

I still remember when my dad was negotiating to buy the 75 Volvo 245DL. He was afraid it meant it was a diesel. I punched the window out, and one day actually went all Hulk under the car and lifted it off the ground. The neighbor across the street had come out to see what all the cursing was about and saw me lift it. . .

[EALm4]

Originally Posted by upstatedoc

Enjoying a nice Cohiba extra vigoroso.

Very nice. Love me a good cigar.

[V1.47fan]

Originally Posted by MrPrena

That is what telemetry softwares are for, but driver do need to go through what it needed to be done.
Yes, depends on type of tires, tire life, front and rear downforce, and 10^2 OTHER variables.

Sounds like you drove an 1.6-2.0L Formula classes in the past?

People use telemetry usually to help tune the suspension, determine best tire pressure etc. Know the limits but That's different than using the formulas you posted.

Next time i take my car to the track, i'll make sure i use those formulas? What U.S. tracks do you need to calculate the limits of the car before hand?

How do you calculate the limits on turns with positive or negative cambers?

[MrPrena]

Originally Posted by V1.47fan

People use telemetry usually to help tune the suspension, determine best tire pressure etc. Know the limits but That's different than using the formulas you posted.

Next time i take my car to the track, i'll make sure i use those formulas? What U.S. tracks do you need to calculate the limits of the car before hand?

How do you calculate the limits on turns with positive or negative cambers?

Formulas are more complicated than this. I don;t know you took enough math/phys to know some can only be solved with numerical method. Meaning labs.
Then why do you think the damn F1 teams test at Jerez and Catalyuna so much?????? Why do you think they have wind tunnels to calculate the wind resistance?

Austin TX? US GP?

Last one, I would recommend you to go online and look at it. Then talk to engineer who designed your suspension (not sissy street racecar M3). Then talk with race car tire manufacturers on how much MECHANICAL GRIP (frictional) grip of net force you can generate PURELY on mechanical grip.

All these questions (at least 1-2), you could've easily achieved the answers by you just browsing the internet.

These are very "low ball fundamental" (for college ME/Phys kids to just comprehend level) physics, but just give you an example...

[V1.47fan]

Originally Posted by MrPrena

Eau Rouge is one area you need to "calculate" with physics to know your and car's limit. I agree.

Most of non-car freaks think lateral acceleration limit @r=x ft is the limit of the lateral "a", but that is just at that radius.

I think our E9x M3 can do about 1.1g at Eau Rouge. Meaning you gotta calculate accordingly, because you gotta go to the other side of the curve, and being 2.2g (hypothetical #) NET lat "a." (you can use a=v^2/r as a start, but real calculation can be severely more complicated).

As being said, with a car with mechanical grip street stock car without significant >g down force cannot go nearly as fast.
Need at least

You find the limits by trial and error, you don't actually calculate the limits of your E9X M3 using a bunch of formulas beforehand. Some people drive well under the limits, others exceed and recover (calculated risks) other cant recover. The key is to be right at the limits.

[1MOREMOD]

All those numbers are theoretical and can be pretty accurate but the cars don't drive in theory. Things change continuously. You can't say I'm gonna enter this corner at x mph and turn y degrees and apply z throttle at point b after trail braking at f-h pressure with release point t and moving my hands at r revolutions per second on unwind? You would wreck in the paddock. As said above its trial and error, math only determines what's possible a person doesn't function that way.

[MrPrena]

Originally Posted by V1.47fan

You find the limits by trial and error, you don't actually calculate the limits of your E9X M3 using a bunch of formulas beforehand. Some people drive well under the limits, others exceed and recover (calculated risks) other cant recover. The key is to be right at the limits.

I haven't raced street cars (only FPs), but open wheel race cars, you initially do pre-run consult with engineers (calculation and other variables) FIRST. Then you run the circuit to see how bunch of "variables" changed on pressure, temp, track temp, etc.
As "having fun at the circuit" can be called "trial and error."
In racing term, it is free practice (FP) to gather the actual info for team engineers and apply it for better set up.

[V1.47fan]

Originally Posted by MrPrena

I haven't raced street cars (only FPs), but open wheel race cars, you initially do pre-run consult with engineers (calculation and other variables) FIRST. Then you run the circuit to see how bunch of "variables" changed on pressure, temp, track temp, etc.
As "having fun at the circuit" can be called "trial and error."
In racing term, it is free practice (FP) to gather the actual info for team engineers and apply it for better set up.

Well, racing an E92 M3, you dont use the formulas you posted to find the car's limits on the track.

[V1.47fan]

Originally Posted by 1MOREMOD

All those numbers are theoretical and can be pretty accurate but the cars don't drive in theory. Things change continuously. You can't say I'm gonna enter this corner at x mph and turn y degrees and apply z throttle at point b after trail braking at f-h pressure with release point t and moving my hands at r revolutions per second on unwind? You would wreck in the paddock. As said above its trial and error, math only determines what's possible a person doesn't function that way.

+1

Even Pro race car drivers dont look at the speedo, maybe the tach even that after a while the car and the driver become one. They can pretty shift within a 100 rpm of redline without looking at the tachometer, going by the engine sound.
If they enter a corner too fast, next lap they might change the initial braking point for that turn.

Most race cars will have a big tach dial in the middle and a small speedo on the side bc it's not important in racing, some don't have speedometers.