Negative Camber; What does this do?

[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.