FWD negative camber effects

[jrustles]

Hey guys, so I have my front camber set at about 3 degrees negative via non-adjustable hardware ie not camber plates. Being a FWD car, understeer was an issue, and the camber has really evened things out a bit, but the problem is, this is a daily driver so how can I manage the side-effects?
For example, I was doing a good 90 on the highway and suddenly grooved pavement out of nowhere. The car began tracking violently, I was struggling to keep it in line going from one side of center to the other.

FTR I don't care about uneven tire wear, in fact I need the tires to wear according to the camber. The tires on there now are worn out, and are only about halfway worn according to the camber. When new tires are put on will the tracking disappear once the tread wears to the angle??

 

[eljefino]

I bet your funky tire wear is adding to your camber troubles. If your rears are worn normally swap 'em around.

 

[Hokiefyd]

Three degrees is an extreme amount of camber. Anything in an alignment measured in single digits of degrees is an extreme amount.

Are you sure you truly have negative three degrees of camber (-3.0 deg)?

 

[bigt61]

Probably a good camber setting for a race car, but not for a street car driven daily. You might mitigate some evil effects by adding some caster and toe in. Any toe out will improve turn in, but make it more darty on uneven surfaces. 3 degrees negative will chew up some new tires quick - running a little more front pressure will help the wear.

 

[Cardenio327]

When you have the car aligned you need to have them set the cross camber to less than 0.20°. The alignment tech probably won't want to do it, but there is usually enough play where the strut fastens to the knuckle to loosen the bolts and pry both tires until the cross camber is less than 1/5 of a degree. It takes quite a bit of practice for an alignment tech to be able to do this without frustration, so most alignment shops are just going to want to do a "toe 'n go". There are eccentric bolts and wedges available that can make the adjustment easier to do as well.

However, the skittering you describe is an effect of high camber, getting the camber even on both sides will only reduce the skittering, not eliminate it.

Once your tires get worn in with an incline in the tread, it will only get worse. The tires will be acting like giant screws, pulling the car independently of camber or caster pulls.

 

[ARCOgraphite]

3 deg is way too much for the street. 1/2 deg is more like it. I was thinking of this as my honda FIT evidences POSITIVE camber and understeers terribly (like and old minivan - NO! - worse). Heav_ier anti roll bars on both ends should help along with hard poly bushings everywhere especially the lower control arm pivot and load bushings and a mild lowering. Add in also Very Slight total toe out and no more than 2deg+ caster ( better at 1.25- 1.5deg+)
Also, Do you have a neutral or neg roll radius geo with the current wheel offset?

 

[Cardenio327]

Originally Posted By: ARCOgraphite
I was thinking of this as my honda FIT evidences POSITIVE camber and understeers terribly (like and old minivan - NO! - worse).


ARCOgraphite, my Fit runs about a third of a degree positive on the front and a full degree negative on the rear. Getting rid of the Pirelli wheelbarrow tires it came with and putting on Potenzas designed for Australia cleaned the handling right up.

 

[ARCOgraphite]

IIRC Mine came with potenzas. Not racy ones though. My DS rear is sagging from my 235lb weight. CAn this be fixed? Is there and elctric steering recalibration to slow the assist? I feel it recal and firm up if I racey onbly to revert to way-overboost when driving around town. Dang, New-fangled E-lectronikk carpfish!

 

[d00df00d]

Originally Posted By: Hokiefyd
Three degrees is an extreme amount of camber. Anything in an alignment measured in single digits of degrees is an extreme amount.

Not caster.

 

[d00df00d]

Originally Posted By: jrustles
Hey guys, so I have my front camber set at about 3 degrees negative via non-adjustable hardware ie not camber plates. Being a FWD car, understeer was an issue, and the camber has really evened things out a bit, but the problem is, this is a daily driver so how can I manage the side-effects?
For example, I was doing a good 90 on the highway and suddenly grooved pavement out of nowhere. The car began tracking violently, I was struggling to keep it in line going from one side of center to the other.

FTR I don't care about uneven tire wear, in fact I need the tires to wear according to the camber. The tires on there now are worn out, and are only about halfway worn according to the camber. When new tires are put on will the tracking disappear once the tread wears to the angle??


Tire wear isn't the only negative consequence. You can expect braking to suffer, too.

Anything else you can do to dial out understeer will also dial in oversteer big time. IMO, your best hope is to go back to stock alignment and get really sticky tires.

Adding caster angle might help. That way, you'll get camber as you steer but not when you're going straight. That'll increase torque steer, though.

If all of that doesn't work and/or isn't feasible... hate to break it to you, but you need a different car.

 

[Cardenio327]

Originally Posted By: ARCOgraphite
IIRC Mine came with potenzas. Not racy ones though. My DS rear is sagging from my 235lb weight. CAn this be fixed? Is there and elctric steering recalibration to slow the assist? I feel it recal and firm up if I racey onbly to revert to way-overboost when driving around town. Dang, New-fangled E-lectronikk carpfish!


About a good 90% of OEM tires are garbage IMO. The Fits around here that came with 15" Bridgestones were equipped with the B381 or B391, about the sorriest excuses for tires ever made. The ones with 16"s come withe Turanza ER300 or ER370, a little better but still weak.

Mine sags when we put 3 or more people in it too. Aftermarket springs maybe? I don't know if there's anything that can be done about the steering, I've just got used to its deadness over time.

 

[SwampSurvivor]

Set the camber back to safe levels and put on a larger rear sway bar.

 

[IndyIan]

Originally Posted By: jrustles
Hey guys, so I have my front camber set at about 3 degrees negative via non-adjustable hardware ie not camber plates. Being a FWD car, understeer was an issue, and the camber has really evened things out a bit, but the problem is, this is a daily driver so how can I manage the side-effects?
For example, I was doing a good 90 on the highway and suddenly grooved pavement out of nowhere. The car began tracking violently, I was struggling to keep it in line going from one side of center to the other.

FTR I don't care about uneven tire wear, in fact I need the tires to wear according to the camber. The tires on there now are worn out, and are only about halfway worn according to the camber. When new tires are put on will the tracking disappear once the tread wears to the angle??


Are you autocrossing the car? I ran about -1.5 on the front of my Neon for AX and with a rear sway bar and it was tossable and fun for autocross but still drove pretty much normally on the street with my 185/65R14 tires. Tire wear was a bit uneven but still pretty reasonable. On my super skinny 155 snow tires, wear was more even again.
If its a mac strut front end, just slot the upper hole that clamps onto the knuckle, then you can have it aligned to something more practical for street use. 1.5 was the most I could get without slotting the bottom hole the other way. I bought a new round file and it didn't take long to remove enough material.
If you insist on keeping the 3 deg of camber, you will actually have to set the front toe out a bit. Zero toe with that camber has the tires fighting each pushing in, some amount of toe out will have them rolling without side forces. You'll have to get into some books on setting up racing suspension to give you some idea of the correct toe setting.
Good luck and don't set up your car so its a handful on the street.

 

[A_Harman]

For a street car, 3 degrees of negative camber is too much. 1-1.5 degrees negative is all that you should run before you start to have a lot of trouble with uneven tire wear.

 

[Hokiefyd]

Originally Posted By: d00df00d
Originally Posted By: Hokiefyd
Three degrees is an extreme amount of camber. Anything in an alignment measured in single digits of degrees is an extreme amount.

Not caster.

Yes, you got me there. Caster is the exception.

 

[randomhero439]

I wouldnt run -3* unless it was a race car. I do alot of autocross and my Accord is only -2* up front and -1* in the rear.

 

[rslifkin]

If you can add some caster, you should be able to run less camber and still keep the good handling. The steering will get heavier though.

 

[The_Jed]

I'd be willing to bet the instability you experienced was a result of the state of the tires combined with (I assume) toe out.
I set the front camber of my Impreza at -2.7 degrees when I used to Autocross. It was my DD at the time. I also a LOT more pressure in the front tires than the rear. If the sidewalls are tall you can get away with and need more camber.
I ran the same street tires with that alignment for just over 2 years and never noticed any odd or accelerated wear. The toe was set completely neutral, neither in nor out, on both ends.
Excessive toe will have a much more detrimental effect on tire life than camber.
If you like it and it handles better, go for it!

 

[OVERKILL]

What kind of car is this?

 

[rslifkin]

Originally Posted By: The_Jed
Excessive toe will have a much more detrimental effect on tire life than camber.


Very true. In addition, if you drive it hard, you can get away with more camber before it starts to wear unevenly as you'll be flexing the tires harder in turns.