Negative Camber; What does this do?

[Ripper]

what exactly does a negative chamber do? and what's it's purpose? does it give you more traction in the front wheels as it turns?

[Tuner]

Negative Camber alone will not. It's a combination of all three Caster, Camber, and Toe

http://autorepair.about.com/gi/dynam...Falignment.htm

[f8ldzz]

It depends on the suspension...
MacPherson strut (front) suspension can use lots of negative camber due to the suspension design.
AE86, S13 / S14, FC3S all use MacPherson front struts.
The negative camber (up front) allows for better grip.
Name of the game is sticky up front...loose in the rear.
Rear nagative camber in the rear is preference.
You see some (D1) drift cars running lots of negative camber in the rear, but this has nothing to do with (more) grip...in fact, it's for *less* grip.
I, personally, don't like wasting tires (hell, can't afford them!) in the rear just on the inside edges just to look cool with wide tires in back.
I try to tune the car with even tire wear in the rear, and this mean very little (negative camber).

Cars like the FD3S, which use double wishbone up front (and back), don't need the excessive negative camber in front.

[chmercer]

i think it should be clarified that increased negative camber gives you more grip only when cornering. when going straight your grip is decreased. running a ton of negative in the back would make your car loose, but it would be harder to hold the drift once you initiate because you have less traction.

[JunpoweR]

Camber

Well depending on your turning and cars roll you will have to set the camber more negative for harder turning and less for normal straight driving..It's mostly for tire patch to contact the road flatter because when ur car turns ir usually rolls so u will have to push the top(negative camber) of the wheels in so when ur car is tilted the tire is flat against the road..

Usually you will need a temp gauge and an open space to test camber.just looking at tire wear wont show much ..Go drive hard for 2-5 minutes and then right when ur at a stop check the tire tempatures and find the hottest part.You will want it to be slightly off center to the outside of the tire..This means you have good camber for the turning youre gonna do..Each track is diffrent so you will have to do this after one run atleast..This is why you have practice laps at almost every event.

[CrazyHawaiian]

Well I'm no expert or anything, but the way I understand it is that negative camber will even out the contact patch while sliding. Pictures are worth a thousand words, so here's a pic to show you what I mean: click me. Check out the pass side front tire. See how it is angled inward? This green car has a regular (street friendly) setup so the camber is not modified for drifting. But if the front wheels had more negative camber then the pass side front tire would be level with the ground (while sliding) and provide a better contact patch to control the car. I hope that helps explain why drifters usually run more negative camber. Its definately not cool for street driving (uneven tread wear), but does make a difference for drifting. But yeah, these guys are right, its not all about camber. Caster and toe also matter.

[GRiDRaceTech]

Sizzearch. I know I personally have covered it numerous times.

[f8ldzz]

Originally posted by JunpoweR
Usually you will need a temp gauge and an open space to test camber.just looking at tire wear wont show much ..

I would disagree.
There is a trick with autocross guys who use white shoe polish on the outside edges to check for tire sidewall "rollover".
This will definitely help if your problem is too much positive camber or overinflation of pressure.

We tend to use R-compound tires for the front, and it's pretty obvious how the tire is wearing across the width of the thread on the track.

Even with regular high-performance street tires, a keen eye will pick-up the signs of uneven tire wear.
The key is to check the tire graining across the width of the tire.
Track surfaces are typically very abrasive, and you should pick-up the wear across the tires tread pretty easily.

[f8ldzz]

Originally posted by CrazyHawaiian
Well I'm no expert or anything, but the way I understand it is that negative camber will even out the contact patch while sliding.

Um, not necessarily.
It's kinda complex, and it has to do with suspension geometry, tire loading, sway bar stiffness, etc.

[JunpoweR]

Originally posted by f8ldzz
I would disagree.
There is a trick with autocross guys who use white shoe polish on the outside edges to check for tire sidewall "rollover".
This will definitely help if your problem is too much positive camber or overinflation of pressure.

I disagree,
Were not trying to pull magic tricks here.You might be able to see how far the tire rolls but you will not be able to see what part gets hot .Abybody can roll over a tire but getting the camber adjusted to the tire will ensure better wear than with just shoe polish..This is ok if you dont have a tempature sensor but to be more exact you will need a temp. sensor to see where the tire gets the hottest..

Making sure the hottest tempatures on the tire are near center or slightly to the outside will really give even wear compared to using shoe polish..Common guys lets keep the shoe polish on the windows or your shoes not your tires..LMAO

[GRiDRaceTech]

Shoe polish: $3.99
Temperature probe: $124.95

Now I know why some of the best autocrossers in the world use shoe polish.

[f8ldzz]

Originally posted by JunpoweR
I disagree,
Were not trying to pull magic tricks here.You might be able to see how far the tire rolls but you will not be able to see what part gets hot .Abybody can roll over a tire but getting the camber adjusted to the tire will ensure better wear than with just shoe polish..This is ok if you dont have a tempature sensor but to be more exact you will need a temp. sensor to see where the tire gets the hottest..

Sure, I'm not disagreeing with a tire pyrometer being the ideal measuring too for this job, but my point is it's not absolutely necessary.
I keep track of both front and rear tires by inspecting them after every run, and this has worked fairly well for us.
We're able to easily tell rear tire wear just by staring at it.
This allows us to adjust tire pressures for better tire wear.
We are running R-compound tires up front, so the softer treadwear might make it easier for us to watch the tread wear.

Making sure the hottest tempatures on the tire are near center or slightly to the outside will really give even wear compared to using shoe polish..Common guys lets keep the shoe polish on the windows or your shoes not your tires..LMAO

Uh ok, cheap shot at drag racers...

[f8ldzz]

Originally posted by GRiDRaceTech
Shoe polish: $3.99
Temperature probe: $124.95

Now I know why some of the best autocrossers in the world use shoe polish.

I don't think it's a fair comparison to compare "best autocrossers" with your typical drift enthusiasts on here...

[GRiDRaceTech]

You mean because the typical drift enthusiast is fourteen years old?

[f8ldzz]

Originally posted by GRiDRaceTech
You mean because the typical drift enthusiast is fourteen years old?

No, that wasn't the implication.
I see the local SCCA guys regularly use tire pyrometers.
I have never seen any of the local drift guys use them.
I don't think I've ever seen any other drifters on video use them.
Do you guys use them?

[tonesdef86]

Ummm i see scca guys use tire temps all the time


tire temp is good so you know that your are running your tire at the right heat temp and that they don't get over heated. IF they do theres less air or more or what ever

THe shoe polish from what i under stand shows the tire wall roll like he said but from what i was told it tells you if your driving to hard if you should slow down Etc etc.

and camber can easily be seen on any performance tire if you can't see it your just a dummy or blind.


Oh and on a side note at high speeds negative camber is bad for braking but ok for top speed. With my -4 the car felt less floaty but stops like crap and fades really fast. the toe i am running kills my high speed and make the car pretty scary to drive. Going side ways on the high way at 90mph in a lot of traffic sucks

[CrazyHawaiian]

I dunno, I dont waste my time with any of this stuff. I dont need any tools to determine if I need to make adjustments. When I'm done drifting I look at my tires and its pretty obvious if the sidewalls are rolling or if the treadwear is uneven. But even then, how the car slides and feels is more important to me than how my tire tread wears or what temps it reaches. And while it may be true that I dont fully use the tires due to uneven tread wear, premature wear, whatever ... so what? This is drifting. Tires will get destroyed.

And I'm gonna stick to what I originally said. Negative camber will even out the contact patch of the outside front tire while sliding. Not enough negative camber and the contact patch will be uneven while sliding, favoring the outside of the tire. Yes its complex, and yes other variables play into what alignment settings you should use, but this isnt voodoo magic. Just looking at your tires after drifting will tell you everything you need to know.

And just to let you know, I have never seen anybody at any of the local drifting events here in Hawaii use tire temp guages or shoe polish or whatever. In fact, I dont know of any drifters that care about tire temps.

[JunpoweR]

I care about tire tempatures!!!
Damm it's hot here!!

Well shoe polish or tire temp. sensor or just by visual either or will help in setting camber ratings and to adjust for tire wear.
I believe camber and tire wear are very important during competition level drifting,since the tires are getting more abuse than in autocrossing or road racing.Just my thoughts.

[AlexPfeiffer]

I think most of you guys have the wrong idea on camber or really have no experience playing with different settings.

First off, your tire is like a rubber band and what you are trying to do is get the most amount of your tire on the ground. So as you turn, the tire has deflection and the body of the car rolls. That means you need to angle your tires to get the middle (biggest part) of the tire on the ground while you are turning instead of riding only on the outside edge.

Tire temps do not work. They only give you a general referance to if your settings or pressures are within reason. They are also inacurate in that you do not get the readings as you are turning (while you are using your tires) but after you finish your run and stop off of the track, the inside should always have the most temp since that is the part that is always in contact with the ground in both directions of turning.

Now you have to factor in drifting and oppsite lock. All cars come with castor. Castor is the angle of your upright or strut. The thing about castor is that as you turn, it changes your camber settings. The more castor you have, the more camber change you will get. As you turn normaly, you will get more camber but this also means that when you drift or turn opposite the corner, your loosing camber. Your inside wheel has now become your outside wheel, so in drifting, you generally want to run more camber and less castor than factory settings.


The truth to all this, you just want your car to be at least decent and all the settings dont mean too much because its still up to you to drive it.

[f8ldzz]

Originally posted by AlexPfeiffer
I think most of you guys have the wrong idea on camber or really have no experience playing with different settings.

You're right!
Suspension tuning is a "black art" that is a complex association of a number of variables.
The thread had specifically narrowed on (negative) camber, and I was trying to keep it on that.
But in reality, it is all inter-related.
You need to look at the whole picture that includes, but not limited to: caster, suspension geometry, suspension design, toe, steering geometry - ackerman or anti-ackerman, bump steer...
It ends up being a big ball of confusion!

One point that AlexPfeiffer made that had been a rage of debate even amoung the SCCA guys is the use of a tire pyrometer.
The argument against is dependent on the track layout.
Tire pyrometers would only measure the last sections of the track that you've just run, and it's not a real good indicator of tire temps across the entire track from start to finish.
The longer and varied the track layout is, the more skewed the data is from the tire pyrometer at the end of the run.

tonesdef86 also mentioned another good point.
Suspension alignment is usually a compromise in handling.
You can tune for a specific section of a track, but you usually sacrifice (handling) in another section.
It is very easy to adjust for grip driving, as track times is your indicator of how well the car is handling (usually).
But for drifting, how do you quantify that?
This is where driver feedback is paramount.

[artika]

For street driving, I would assume a 0-to- -1 degree negative camber would be preferable... for us people of high speeds, I'm sure that cornering (not necessarily drifting.. talking grip here) is a big thing for you.

A common problem with us Datsun 510'ers is positive camber. 510's naturally understeer. They had a stock positive camber (memory serves, do not quote me!) from the factory with those little 4" wide tires that were practically useless except for groceries (Glad it's post-90's!). A very common swap is the 280zx front strut conversion, which consists of (variables through the years) camber change. Some years (I believe early 80's) had excessive positive camber in conjunction with the 510, and that's bad... so they use camber plates and blah blah.

But if I were to run a street-only car, I'd run ever so slighly negative camber. That way in mid-corner the inside tire gets a firm patch of rubber against the surface as opposed to scraping along with the outside... and on the inside as the front of the car goes down, or the car leans to one side (again, swaybar variables intervene with thought) the inside tire gains a stronger, firmer patch of tread. Street driven cars don't see xtreme cornering very often as opposed to track-day cars. You have to find what is comfortable with YOUR CAR, and YOUR driving style.

If we ran positive camber, the outside portion of the outside tire would be the only thing gripping (ie. UNDERSTEER) and the inside tire wouldn't be helping much either. This is why autocrossers use very strong negative camber.

A friend that autocrosses his 240z, uses something like -6 degrees camber up front and stock in the rear. The car handles like it's on rails when going through the cones. He also has super stiff coils all the way around, big front and rear swaybar, etc. Fully modified autocrossing machine. But that's a different post for another time ;-)
___

Now heres something to think about.
How do you counteract the effect variable camber change during load? A Datto 510 comes with IRS.. that's Independent. And as the rear of the car goes down, more negative camber is a result. I'm running stock rate springs all the way around @ Stock ride height as well. Through the corners, the outside tire (the one that has the most load) has mass negative camber... this allows that tire to have a nice big fatty patch of rubber attatched to the pavement, while the inside (less load) has positive camber due to the body rising. With that in mind, the inside tire, with it's positive camber, is keeping a fair amount of rubber attatched as well. A good simple design for suspensions. This is where spring rates come in and blah blah... I could go on for days.

SIMPLE FINISH:
Autocross: Negative Camber
Racetrack: Slight Negative Camber
Street: Zero to Slight Negative Camber


Okay.. and I didn't mention castor/toe etc because this is a CAMBER thread. Not a Castor/Toe thread.

[JunpoweR]

Originally posted by artika

SIMPLE FINISH:
Autocross: Negative Camber
Racetrack: Slight Negative Camber
Street: Zero to Slight Negative Camber


Okay.. and I didn't mention castor/toe etc because this is a CAMBER thread. Not a Castor/Toe thread.

Well said Artika =D

[CrazyHawaiian]

Yeah except for the fact that this is DRIFTING.com and only a small portion of this thread has to do with DRIFTING. Forget about all this suspension theory, what do SCCA guys do, OMG my tire temps are uneven, blah blah blah. Go take the car out and drift, use up some rubber, try different settings, feel the differences, and then maybe you'll understand what Alex said - "The truth to all this, you just want your car to be at least decent and all the settings dont mean too much because its still up to you to drive it." I totally agree ...

[artika]

Yep Yep.
No desputes there, either.