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      04-10-2011, 08:44 PM   #1
DaFish
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STILL understeering at limit - there is more in the car I know it

Well, I thought I would start a thread on the amount of AT THE LIMIT understeer still in the car after the following:

1) Dinan Stage THREE - Dinan Front sway, Dinan springs/shocks all round, and the Dinan camber plates - PLUS

2) M3 Tension rods and M3 Wishbones (I added those)

I must be running over negative 2 degrees of front camber

3) 1 size up on NON RFTs - Bridgestone Pole Position tires (235/265 - on 19" stock 230 rims)

I guess it is stilll good that the car understeers not oversteers, but I certainly feel there are more G's can be pulled in this car that what I can currently do. I noticed in a long tight on ramp - 270 degrees, the front is losing traction still and pushing.

COMING: Rear subframe bushings, REAR Dinan Sway Bar, Wavetrac LSD

My questions to the communitity are as follows:

Q1) How much difference will there be when I add the three items listed above?

Q2) Do you believe the front strut bar would be a good addition to my Mods? Why?

Q3) Stagger: I think the Stagger is really increasing the amount of understeer and the weight of the car is overwhelming the 235 front tires - regardless of the mods.

What will give me the biggest bang for the buck to get some more G's?
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      04-10-2011, 09:58 PM   #2
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Remove the front rear stagger. That is by far the best bang for buck. I have Dinan stage 3 with rear sway. The understeer only went away after I reduced the stagger.
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      04-11-2011, 12:01 AM   #3
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255s all around did it for me
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      04-11-2011, 12:30 AM   #4
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I've heard a staggered setup is the usual culprit for understeer. Didn't stop me from running staggered however.
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      04-11-2011, 09:09 AM   #5
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Originally Posted by e90pilot View Post
Remove the front rear stagger. That is by far the best bang for buck. I have Dinan stage 3 with rear sway. The understeer only went away after I reduced the stagger.
Thanks E90Pilot... we have spoken about this before too....

It is going to cost me another 5k min to get rims and tires. i would go michelin Super Sports - that I have decided, but not the rim.

I prefer the 19", but the 18" are better handlers. I am doing the rear end work regardless...

I may have a line on some Dinan rims - that is a good option too - probably the biggest set of rubber on the front that I have seen people do, but I am not crazy about the look of the rims. I like more concavity than the Dinan rims.

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255s all around - one what size rims? - gotta be 9" for sure. What offsets on front and back?

can you make a all square setup LOOK staggered with offsets? OR at least some good concavity. Please advise what you went with and what it cost.

is 10mm stagger 255/265 going to be alright or just square.... for handling?
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      04-11-2011, 11:38 AM   #6
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255's fit on 8.5" rims.. that's what the stock rears are on sports package cars, which run 255 tires. If you are worried about the look of the rear offset, you can put some 10 or 12mm spacers back there also.
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      04-11-2011, 11:44 AM   #7
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255's fit on 8.5" rims.. that's what the stock rears are on sports package cars, which run 255 tires. If you are worried about the look of the rear offset, you can put some 10 or 12mm spacers back there also.
Has anybody tried getting the REAR 230 rims to fit on the FRONT with spacers? Would this work at all?


This would make it all square setup, I love the look of the 230 rims, and they have really nice concavity.

I could get 2 knock off 230 rims inexpensively. this would be a very cheap option for me.... if it worked.
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      04-11-2011, 11:46 AM   #8
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You're not going to like this.

Whenever someone says there's still "understeer" at the limit, it usually raises a flag in my head that says "said poster has no idea what understeer is."

Figure out WHERE this so called understeer is coming from "at the limit." Meaning if it's at corner entry or corner exit, will come in very handy in how it's actually fixed. If you can't tell me where it's coming from there's no point trying to pin-point a specific component to fix it.

And to be completely BLUNT, A fix for a single corner isn't going to work for all the corners on a course. If you're telling me the car is understeering at the exit of a particular turn on a certain track, you still MUST weight the entire track as an overall solution and fix/tune to neutralize the chassis for the entire track. Saying "my car still understeers" is absolutely meaningless.

Take Buttonwillow, for example. I can tell you that my car as is currently set up will understeer INTO Buttonhook, turn 2 in the full-course configuration going clockwise. I can certainly stiffen up the rear to give up some grip in the back to force it to go neutral for turn 2, but the end result is that the car will have a tendency to OVERSTEER at Star Mazda, which leads to the FASTEST section of the track. Fixing for "understeer" upon corner entry at turn 2 is pointless. The speed I gain there will be promptly lost back at Star Mazda since at the end of the next complex you're looking at speeds in excess of 120mph, while at best, exiting Buttonhook leads to a short straight that sees the top of 3rd gear (about 90mph). So if it makes it harder to navigate Star Mazda at high speed consistently, I'll be happy to deal with corner entry understeer for Buttonhook by giving up some more speed going into it.
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      04-14-2011, 01:30 PM   #9
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Is this a daily driver only or a Track day car?
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      04-14-2011, 02:24 PM   #10
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Originally Posted by The HACK View Post
You're not going to like this.
No issues... I take what you say at face value... bring it on.

Quote:
Originally Posted by The HACK View Post
Whenever someone says there's still "understeer" at the limit, it usually raises a flag in my head that says "said poster has no idea what understeer is."
"What is "Understeer"?
Letís say that you are driving on an icy street. You are going straight, but there is a corner coming up, so you turn your steering wheel. You turn it as you would normally, but your car just barely begins to turn.

This is called Understeer.

Basically, the term Understeer means that you have to give your car more steering input than the corner should require to get it to go around. The advantage of this is that your car is usually very stable in a straight line, but you have to work harder to get the car to turn.

For a more scientific definition, imagine that we draw a tangent line to the circle that the car is traveling around. If you have to turn the front wheels so that they are at a more aggressive angle (pointed more to center) than the tangent line, your car tends toward Understeer.

Hereís another way to think of Understeer. If you are driving around in a circle of constant radius, and you start accelerating, your front tires will be the first to lose traction, which will increase the radius of the circle."

The passage above I copied from:
http://flatironsrally.typepad.com/fa...s-underst.html

This is exactly what I experience. "front tires will be the first to lose traction, which will increase the radius of the circle"

Quote:
Originally Posted by The HACK View Post
Figure out WHERE this so called understeer is coming from "at the limit."
1) I have a 270 degree on ramp I go around all the time.... smooth, fast, no cops.... beautiful.

- I go in quick - possibly too quick - but no initial understeer as described above and the car is on balance.
- around 90 degrees the front push starts and continues into the corner. I try to keep acceleration neutral, not pushing with the larger rears (which I think is the prob). I feel the front tires fold over and that is when I lose even more traction, and the front steering wheel angle has to be increased to keep line. I have to back off speed to regain line when front grip returns. This is "fun killing, speed killing. I want this fixed.

QUESTION: Will a front strut brace help this?

2) Corner entry - initially has understeer, I can feel the fronts slide - I maybe going too fast in as you mentioned. If I go slower in, and get the car set on the corner, I can hold more corner speed throughout.
I am talking about a 90 degree street corner... before I did the mods, the fronts would plow terribly, overwhelming the tires -at what I thought was a slow speed.

- This issue has been dramatically improved with the addition of my camber (over neg 2 degrees).
- I think with the new dinan sways coming, it will be better again - QUESTION: By how much?
- I think if I had more meat in the front and a square setup - it would be better again - E90Pilot thinks this is the fix - I agree but it is expensive.

QUESTION: Will a front strut brace help this?

Quote:
Originally Posted by The HACK View Post
And to be completely BLUNT, A fix for a single corner isn't going to work for all the corners on a course. If you're telling me the car is understeering at the exit of a particular turn on a certain track, you still MUST weight the entire track as an overall solution and fix/tune to neutralize the chassis for the entire track. Saying "my car still understeers" is absolutely meaningless.
that is what i want to fix anyway. I don't think it will affect the rest of the types of corners negatively.

It is also a "standard" fix... the sway bar is coming anyway so I will see. Should I do the strut bar at the same time, or save the money for the rims and tires - uugh...
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      04-14-2011, 03:18 PM   #11
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Have you tried playing around with tire pressures?

I know if you increase tire pressure in the front, you increase oversteer. More pressure up front results in less sidewall roll which allows for a larger usable contact patch.

And lowering tire pressure in the rear will encourage oversteer. But with a staggered setup, this might not apply.

Just make sure you don't exceed the max psi rating on your tires. And remember that the pressure in the tires will increase with speed because of friction. So when you set your tires, set them at least 7-8 psi below the max rating to accommodate the expansion of moisture in the air.
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      04-14-2011, 03:19 PM   #12
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Quote:
Originally Posted by DaFish
No issues... I take what you say at face value... bring it on.

"What is "Understeer"?
Let’s say that you are driving on an icy street. You are going straight, but there is a corner coming up, so you turn your steering wheel. You turn it as you would normally, but your car just barely begins to turn.

This is called Understeer.
WRONG. This is called corner entry understeer. It means the car does not respond to steering input prior to entering a turn. There are multiple ways to cure this. First, is human error. You are entering the turn too fast for the given amount of traction available to you. To cure it, simply enter the turn at a slower speed.

Quote:
Originally Posted by DaFish
Basically, the term Understeer means that you have to give your car more steering input than the corner should require to get it to go around. The advantage of this is that your car is usually very stable in a straight line, but you have to work harder to get the car to turn.

For a more scientific definition, imagine that we draw a tangent line to the circle that the car is traveling around. If you have to turn the front wheels so that they are at a more aggressive angle (pointed more to center) than the tangent line, your car tends toward Understeer.

Here’s another way to think of Understeer. If you are driving around in a circle of constant radius, and you start accelerating, your front tires will be the first to lose traction, which will increase the radius of the circle."

The passage above I copied from:
http://flatironsrally.typepad.com/fa...s-underst.html
It's on the internet, therefore it must be the truth...

S.I.G.H.

There you go. You have little to no concept of what "understeer" actually means. What you've quoted, is a "text book" example of what understeer's symptom is. If I were to trying to describe understeer to someone who has absolutely no concept of what understeer means, that is what I would use.

It's the equivalent to, say, someone who has never watched or played baseball, and trying to explain to them why you shouldn't swing at every pitch. Well, the goal is to hit the ball somewhere, right?

There are multiple REASONS why understeer occur. At multiple locations of a single TURN. And the way to "cure" it will differ in every situation for every turn at every location. There is no simple "cure" for understeer. THAT, is what you don't understand and why I can't explain to you how to cure your understeer. The plain and simple truth is, a suspension system and how a car behaves at the limit of traction is dynamic, meaning there are multiple variables at work here.

Starting from the most simple and most basic, 99.95% of "understeer" is human error. Once you fix that part, the rest of the .05% of understeer can be fixed in the following manner: Add grip to the end that looses grip first, or take away grip from the end that still has it. And then, you have to figure out if the understeer happens at corner entry, corner exit, under throttle and HOW MUCH under throttle. If you can pin point where and when it's understeering and how, then you have a shot at fixing it.

Quote:
Originally Posted by DaFish
This is exactly what I experience. "front tires will be the first to lose traction, which will increase the radius of the circle"
I'm going to try and explain to you something about chassis dynamics...I've tried to do this multiple times on various forums, and I've come to the conclusion that this is something impossible to grasp over a screen with me typing on a keyboard. So this WILL be the last time I ever attempt this. If you don't get it, I understand. This is something that can only be taught ON A SKID PAD and no amount of reading will ever replace actual experience with someone in the passenger seat pointing out to you what chassis dynamics is, weight transfer means, and when you're actually really understeering.

ALL CARS, no matter how well it's set up, will move away from that centerline tangent when you add throttle. ALL. Every single one. It's a simple physical law that can not and will not be defied in this universe. Acceleration force can only be applied in a straight line, when you're in a static circle, increasing your speed without adding steering will simply result in that static circle becoming larger, since acceleration forces will simply push you away from the apex.

That, is NOT understeer. It's the reason why Earth orbit around the Sun in a fairly consistent distance. If an external force is to be exerted on Earth to speed it up, the radius of the orbit will increase. It is what it is. Doesn't mean Earth is understeering from the Sun. In order to keep the same radius as Earth speeds up, another external force will need to be applied perpendicular to the orbit to keep the same orbit.

What understeer (or oversteer) REALLY is, is when NO AMOUNT OF STEERING INPUT will change the direction of the car. Meaning the front tires are now in a state of kinetic friction in relation to the ground. Meaning that you can no longer travel in a curve in relation to the turn, and the car basically will go in a straight line no matter how much steering input you give it...Not at least until the car slowed down enough for the front tires to regain traction.

Quote:
Originally Posted by DaFish
1) I have a 270 degree on ramp I go around all the time.... smooth, fast, no cops.... beautiful.

- I go in quick - possibly too quick - but no initial understeer as described above and the car is on balance.
- around 90 degrees the front push starts and continues into the corner. I try to keep acceleration neutral, not pushing with the larger rears (which I think is the prob). I feel the front tires fold over and that is when I lose even more traction, and the front steering wheel angle has to be increased to keep line. I have to back off speed to regain line when front grip returns. This is "fun killing, speed killing. I want this fixed.

QUESTION: Will a front strut brace help this?

2) Corner entry - initially has understeer, I can feel the fronts slide - I maybe going too fast in as you mentioned. If I go slower in, and get the car set on the corner, I can hold more corner speed throughout.
I am talking about a 90 degree street corner... before I did the mods, the fronts would plow terribly, overwhelming the tires -at what I thought was a slow speed.

- This issue has been dramatically improved with the addition of my camber (over neg 2 degrees).
- I think with the new dinan sways coming, it will be better again - QUESTION: By how much?
- I think if I had more meat in the front and a square setup - it would be better again - E90Pilot thinks this is the fix - I agree but it is expensive.

QUESTION: Will a front strut brace help this?
I'm going to answer your last question first. You WILL be offended. I'm not going to sugarcoat anything.

No a strut brace won't help you. What will help you is some advanced driver training or high performance driving schools.

What you have described is a classic case of "fast in, slow out." You have to kill your corner exit speed because your corner entry speed is too high. The faulty part here, is the actual driver, not the car. More camber or more tire up front will only improve speed through the middle part of the turn and at the exit, but when you have already blown the corner entry, nothing you do will improve upon mid corner speed and corner exit speed. If you can't maximize mid corner speed and corner exit speed based on your current set-up, no amount of tinkering will ultimately solve your "understeer" problem, because as your speed picks up due to the modifications, you will still ultimately find your limit upon corner entry and run out of skill/talent, except when this happens, it'll be at a much higher speed, a speed you're not familiar with and will not be able to correct.

I am going to leave you with one final nugget of wisdom, because I don't think I'll ever be able to get through to you. Your car, as is right now, is far more neutral and far more capable than you ever will be able to take advantage of without some proper training. The more grip you actually add to your car, will only move that limit up that much higher. The end result will be that it'll come a time where you will have exceeded it's grip limit and when that time comes, you will destroy your car. It's not a pleasant thing for me to say, but it will happen. And when it does, I hope the passive safety systems on the car will keep you alive.

Actually I'll leave you with two nuggets of wisdom. I used to have a buddy who played some minor league baseball. One time we went to a batting cage, and he was stroking 90+ mph pitches easily. I mean it looked so easy so I ask if I can give it a try. Out of 20 pitches I fouled off one, and it made my hand hurt like a motherf**k. Heck I moved over to the 70 mph slow pitch stuff and maybe connected a couple of times for weak ground balls. So we got to talking about the "fine-art" of hitting a ball, and he was telling me that my form and swing actually looked okay, but the part of hitting that takes effort, training, and doing it on a daily basis, the hand/eye coordination, the anticipation, the weight transfer from the leg to the hip to the arm then wrist, the timing...etc, none of that can be learned by just watching. And that when it comes to REAL pitchers, once they started locating pitches and change speeds, it becomes 100X harder to hit.

Driving, especially performance driving, is a lot like that. Except the risks are much higher.

Actually, screw that. I'm going to give you one more nugget of wisdom. I'm kind and generous like that. If and when you actually comprehend this one, you'll have at least made it half way to curing your understeer problems. Your problem, is you move your hands too fast. Slow down your hands, start turning earlier, but turn the steer wheel slower, will cure UNDERSTEER.
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No way I'd ever take my BMW to the track.
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      04-14-2011, 03:26 PM   #13
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your upcoming improvements will not change that much... I would recommend you to go to 255 square. This for me had the biggest impact. Stiffing up the rear will only give you less traction and a more "snappy" rear. The LSD is a great, but creates even more grip in the rear.
I would forget about the rear ARB and first try the square set-up, especially as a daily driver.
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      04-14-2011, 03:34 PM   #14
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Quote:
Originally Posted by The HACK View Post
WRONG. This is called corner entry understeer. It means the car does not respond to steering input prior to entering a turn. There are multiple ways to cure this. First, is human error. You are entering the turn too fast for the given amount of traction available to you. To cure it, simply enter the turn at a slower speed.



It's on the internet, therefore it must be the truth...

S.I.G.H.

There you go. You have little to no concept of what "understeer" actually means. What you've quoted, is a "text book" example of what understeer's symptom is. If I were to trying to describe understeer to someone who has absolutely no concept of what understeer means, that is what I would use.

It's the equivalent to, say, someone who has never watched or played baseball, and trying to explain to them why you shouldn't swing at every pitch. Well, the goal is to hit the ball somewhere, right?

There are multiple REASONS why understeer occur. At multiple locations of a single TURN. And the way to "cure" it will differ in every situation for every turn at every location. There is no simple "cure" for understeer. THAT, is what you don't understand and why I can't explain to you how to cure your understeer. The plain and simple truth is, a suspension system and how a car behaves at the limit of traction is dynamic, meaning there are multiple variables at work here.

Starting from the most simple and most basic, 99.95% of "understeer" is human error. Once you fix that part, the rest of the .05% of understeer can be fixed in the following manner: Add grip to the end that looses grip first, or take away grip from the end that still has it. And then, you have to figure out if the understeer happens at corner entry, corner exit, under throttle and HOW MUCH under throttle. If you can pin point where and when it's understeering and how, then you have a shot at fixing it.



I'm going to try and explain to you something about chassis dynamics...I've tried to do this multiple times on various forums, and I've come to the conclusion that this is something impossible to grasp over a screen with me typing on a keyboard. So this WILL be the last time I ever attempt this. If you don't get it, I understand. This is something that can only be taught ON A SKID PAD and no amount of reading will ever replace actual experience with someone in the passenger seat pointing out to you what chassis dynamics is, weight transfer means, and when you're actually really understeering.

ALL CARS, no matter how well it's set up, will move away from that centerline tangent when you add throttle. ALL. Every single one. It's a simple physical law that can not and will not be defied in this universe. Acceleration force can only be applied in a straight line, when you're in a static circle, increasing your speed without adding steering will simply result in that static circle becoming larger, since acceleration forces will simply push you away from the apex.

That, is NOT understeer. It's the reason why Earth orbit around the Sun in a fairly consistent distance. If an external force is to be exerted on Earth to speed it up, the radius of the orbit will increase. It is what it is. Doesn't mean Earth is understeering from the Sun. In order to keep the same radius as Earth speeds up, another external force will need to be applied perpendicular to the orbit to keep the same orbit.

What understeer (or oversteer) REALLY is, is when NO AMOUNT OF STEERING INPUT will change the direction of the car. Meaning the front tires are now in a state of kinetic friction in relation to the ground. Meaning that you can no longer travel in a curve in relation to the turn, and the car basically will go in a straight line no matter how much steering input you give it...Not at least until the car slowed down enough for the front tires to regain traction.



I'm going to answer your last question first. You WILL be offended. I'm not going to sugarcoat anything.

No a strut brace won't help you. What will help you is some advanced driver training or high performance driving schools.

What you have described is a classic case of "fast in, slow out." You have to kill your corner exit speed because your corner entry speed is too high. The faulty part here, is the actual driver, not the car. More camber or more tire up front will only improve speed through the middle part of the turn and at the exit, but when you have already blown the corner entry, nothing you do will improve upon mid corner speed and corner exit speed. If you can't maximize mid corner speed and corner exit speed based on your current set-up, no amount of tinkering will ultimately solve your "understeer" problem, because as your speed picks up due to the modifications, you will still ultimately find your limit upon corner entry and run out of skill/talent, except when this happens, it'll be at a much higher speed, a speed you're not familiar with and will not be able to correct.

I am going to leave you with one final nugget of wisdom, because I don't think I'll ever be able to get through to you. Your car, as is right now, is far more neutral and far more capable than you ever will be able to take advantage of without some proper training. The more grip you actually add to your car, will only move that limit up that much higher. The end result will be that it'll come a time where you will have exceeded it's grip limit and when that time comes, you will destroy your car. It's not a pleasant thing for me to say, but it will happen. And when it does, I hope the passive safety systems on the car will keep you alive.

Actually I'll leave you with two nuggets of wisdom. I used to have a buddy who played some minor league baseball. One time we went to a batting cage, and he was stroking 90+ mph pitches easily. I mean it looked so easy so I ask if I can give it a try. Out of 20 pitches I fouled off one, and it made my hand hurt like a motherf**k. Heck I moved over to the 70 mph slow pitch stuff and maybe connected a couple of times for weak ground balls. So we got to talking about the "fine-art" of hitting a ball, and he was telling me that my form and swing actually looked okay, but the part of hitting that takes effort, training, and doing it on a daily basis, the hand/eye coordination, the anticipation, the weight transfer from the leg to the hip to the arm then wrist, the timing...etc, none of that can be learned by just watching. And that when it comes to REAL pitchers, once they started locating pitches and change speeds, it becomes 100X harder to hit.

Driving, especially performance driving, is a lot like that. Except the risks are much higher.

Actually, screw that. I'm going to give you one more nugget of wisdom. I'm kind and generous like that. If and when you actually comprehend this one, you'll have at least made it half way to curing your understeer problems. Your problem, is you move your hands too fast. Slow down your hands, start turning earlier, but turn the steer wheel slower, will cure UNDERSTEER.
Bump for common sense
I read, and understood all of this.
Not difficult
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      04-14-2011, 03:39 PM   #15
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Fantastic post HACK. OP, you should read Ross Bentley's book "Speed Secrets". Ross even has a fun anecdote about an "understeering" Indy car, he ends up finding it was a driver issue, not a car setup issue. One other thing, DON'T turn the steering wheel more to decrease your turning radius when you're reaching your front tire's limits. You're going to make it worse! You really ~did~ define "Fast In, Slow out.".
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      04-14-2011, 03:43 PM   #16
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Quote:
Originally Posted by The HACK View Post
WRONG.
lol... you crack me up man. I'll respond when I have a bit more time. Thank God you sugar coated it...
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      04-14-2011, 03:53 PM   #17
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Quote:
Originally Posted by The HACK View Post
WRONG. This is called corner entry understeer. It means the car does not respond to steering input prior to entering a turn. There are multiple ways to cure this. First, is human error. You are entering the turn too fast for the given amount of traction available to you. To cure it, simply enter the turn at a slower speed.



It's on the internet, therefore it must be the truth...

S.I.G.H.

There you go. You have little to no concept of what "understeer" actually means. What you've quoted, is a "text book" example of what understeer's symptom is. If I were to trying to describe understeer to someone who has absolutely no concept of what understeer means, that is what I would use.

It's the equivalent to, say, someone who has never watched or played baseball, and trying to explain to them why you shouldn't swing at every pitch. Well, the goal is to hit the ball somewhere, right?

There are multiple REASONS why understeer occur. At multiple locations of a single TURN. And the way to "cure" it will differ in every situation for every turn at every location. There is no simple "cure" for understeer. THAT, is what you don't understand and why I can't explain to you how to cure your understeer. The plain and simple truth is, a suspension system and how a car behaves at the limit of traction is dynamic, meaning there are multiple variables at work here.

Starting from the most simple and most basic, 99.95% of "understeer" is human error. Once you fix that part, the rest of the .05% of understeer can be fixed in the following manner: Add grip to the end that looses grip first, or take away grip from the end that still has it. And then, you have to figure out if the understeer happens at corner entry, corner exit, under throttle and HOW MUCH under throttle. If you can pin point where and when it's understeering and how, then you have a shot at fixing it.



I'm going to try and explain to you something about chassis dynamics...I've tried to do this multiple times on various forums, and I've come to the conclusion that this is something impossible to grasp over a screen with me typing on a keyboard. So this WILL be the last time I ever attempt this. If you don't get it, I understand. This is something that can only be taught ON A SKID PAD and no amount of reading will ever replace actual experience with someone in the passenger seat pointing out to you what chassis dynamics is, weight transfer means, and when you're actually really understeering.

ALL CARS, no matter how well it's set up, will move away from that centerline tangent when you add throttle. ALL. Every single one. It's a simple physical law that can not and will not be defied in this universe. Acceleration force can only be applied in a straight line, when you're in a static circle, increasing your speed without adding steering will simply result in that static circle becoming larger, since acceleration forces will simply push you away from the apex.

That, is NOT understeer. It's the reason why Earth orbit around the Sun in a fairly consistent distance. If an external force is to be exerted on Earth to speed it up, the radius of the orbit will increase. It is what it is. Doesn't mean Earth is understeering from the Sun. In order to keep the same radius as Earth speeds up, another external force will need to be applied perpendicular to the orbit to keep the same orbit.

What understeer (or oversteer) REALLY is, is when NO AMOUNT OF STEERING INPUT will change the direction of the car. Meaning the front tires are now in a state of kinetic friction in relation to the ground. Meaning that you can no longer travel in a curve in relation to the turn, and the car basically will go in a straight line no matter how much steering input you give it...Not at least until the car slowed down enough for the front tires to regain traction.



I'm going to answer your last question first. You WILL be offended. I'm not going to sugarcoat anything.

No a strut brace won't help you. What will help you is some advanced driver training or high performance driving schools.

What you have described is a classic case of "fast in, slow out." You have to kill your corner exit speed because your corner entry speed is too high. The faulty part here, is the actual driver, not the car. More camber or more tire up front will only improve speed through the middle part of the turn and at the exit, but when you have already blown the corner entry, nothing you do will improve upon mid corner speed and corner exit speed. If you can't maximize mid corner speed and corner exit speed based on your current set-up, no amount of tinkering will ultimately solve your "understeer" problem, because as your speed picks up due to the modifications, you will still ultimately find your limit upon corner entry and run out of skill/talent, except when this happens, it'll be at a much higher speed, a speed you're not familiar with and will not be able to correct.

I am going to leave you with one final nugget of wisdom, because I don't think I'll ever be able to get through to you. Your car, as is right now, is far more neutral and far more capable than you ever will be able to take advantage of without some proper training. The more grip you actually add to your car, will only move that limit up that much higher. The end result will be that it'll come a time where you will have exceeded it's grip limit and when that time comes, you will destroy your car. It's not a pleasant thing for me to say, but it will happen. And when it does, I hope the passive safety systems on the car will keep you alive.

Actually I'll leave you with two nuggets of wisdom. I used to have a buddy who played some minor league baseball. One time we went to a batting cage, and he was stroking 90+ mph pitches easily. I mean it looked so easy so I ask if I can give it a try. Out of 20 pitches I fouled off one, and it made my hand hurt like a motherf**k. Heck I moved over to the 70 mph slow pitch stuff and maybe connected a couple of times for weak ground balls. So we got to talking about the "fine-art" of hitting a ball, and he was telling me that my form and swing actually looked okay, but the part of hitting that takes effort, training, and doing it on a daily basis, the hand/eye coordination, the anticipation, the weight transfer from the leg to the hip to the arm then wrist, the timing...etc, none of that can be learned by just watching. And that when it comes to REAL pitchers, once they started locating pitches and change speeds, it becomes 100X harder to hit.

Driving, especially performance driving, is a lot like that. Except the risks are much higher.

Actually, screw that. I'm going to give you one more nugget of wisdom. I'm kind and generous like that. If and when you actually comprehend this one, you'll have at least made it half way to curing your understeer problems. Your problem, is you move your hands too fast. Slow down your hands, start turning earlier, but turn the steer wheel slower, will cure UNDERSTEER.

well written and on the money. (one again)
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      04-14-2011, 04:20 PM   #18
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Lots of good stuff here. My friend always said the best modification is the driver. I used to think my 350Z understeered like a pig until I found out I was doing it wrong. When I moved to the E90 the front washed no matter what I did. I though it was me again so tried handing the car off to someone who actually know more than I do. He said, "dude, your car understeers... Bad." What really bothered me about my car was the fact that the usual bag of trick to bring the nose back in didn't work. You'd lift, nothing, you remove steering, nothing, brake, nothing. To get the tail work (not even slide) you had to be drastic like drop the outside rear tire off the track on turn-in. I've been to a couple of driving schools so I'm at the point now where I know enough to get myself into trouble. I took the stagger out and now I can much more easily control the car with my feet. It still defaults to understeer but you can manipulate it into oversteer where you need it.

Hack, you're pretty good at explaining complex and dynamic concepts in a simple way. I really don't think you should stop. You might be blunt but you're only offensive to people who aren't open to criticism. I'm a flight instructor and I can pick up that quality in people. This is also the internet and people should be ready to receive some flack.
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      04-14-2011, 05:32 PM   #19
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Beautiful HACK. I understood everything and even learned something. Just beautiful.
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      04-14-2011, 05:46 PM   #20
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Quote:
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Bump for common sense
I read, and understood all of this.
Not difficult
Well, yeah. You're from Denmark. The land where they ALL know how to properly control a drift through a corner. Aren't like all of you people born to be World Rally Championship drivers anyway?

Or am I thinking of Finland?
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      04-14-2011, 08:47 PM   #21
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Nice long post but VERY informative. Thank you for taking the time to write that.
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      04-15-2011, 12:05 AM   #22
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i have a friend that should really read that.
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