-2.5* camber... wreck my tires or no?

[jaymac]

I had my H&R Street Performance coilovers installed last week. Finally made it to the tire shop for an alignment this week. The only #'s out of spec are front camber, naturally. The best they could do was -2.5 drivers, -2.3 passengers. Obviously, I don't have adjustable UCA's. How bad is this for my tires? Early death? Or do-able?
I know everyone has different opinions, so please, feel free.
Thanks,
Jeremy

[A4 Quattro]

I tend to say anything greater than -2° is going to start eating through tires faster. Check where the tires are on a monthly basis and see if the camber wear is increasingly noticeable. If it is, it's time for AUCA.

[jaymac]

I will definitely be keeping an eye on them. I do ALOT of miles (~30K a year), so I will be going through tires fast enough without losing them prematurely due to excess camber.

[S5xy]

It's ok. Overkill for street driving if you don't track/autocross, but won't kill your tires that much quicker. Rotate when you can (even if that means unmounting the tires to the other side if they're directional).

Situations like this, having your toe alignment off will kill your tires the most when coupled with that amount of negative camber, so make sure your toe specs are ok.

[GotRS?]

Situations like this, having your toe alignment off will kill your tires the most when coupled with that amount of negative camber, so make sure your toe specs are ok.

Absolutely! The toe in/out is the killer and you don't even see it happening. Make a point to really check those inside walls regularly.

[Du Werke]

camber doesn't wear tires prematurely, toe does. If your toe is in spec, you have nothing to worry about.

[JamesRS5]

If you're driving 30k miles a year then I'd be investing in some adjustable UCA's. My worry is the contact area of the tires when you're driving in a straight line has now been reduced so you have a car with less grip on the front end!
You've got a great setup for the track where the loaded outside wheel will now have larger contact area in a corner but for a car that's used predominantly on the road, I think the cost of the UCA's would justified not only in the savings on worn tires but also from a safety point of view, excessive camber on the front will make the car more susceptible to tram lining and torque steer under acceleration.

[Du Werke]

AUCA's are completely irrational to correct -2.5 degrees of camber unless being fixated on the number zero keeps you from sleeping at night or the look bothers you.

My worry is the contact area of the tires when you're driving in a straight line has now been reduced

You're kidding right?

I think the cost of the UCA's would justified not only in the savings on worn tires

CAMBER DOESN'T WEAR TIRES IF YOUR TOE IS ALIGNED TO SPEC.

[JamesRS5]

Du Werke,

No I'm not kidding and I don't believe there is any reason to shout?

If you can provide some sound engineering evidence/knowledge to support your claim of excess camber doesn't wear tires then I will apologies to everyone here for stating an incorrect fact, however, you are partially correct, excessive camber and toe will wear tires faster (and I'm talking in a matter of weeks) but excessive camber alone will wear tires and does reduce the contact patch of the tire no matter what your toe angle is,

At the end of the day jaymac, it's your choice, if it were my car, I'd be fitting the UCA's

Here's a little info for you Jaymac, it's an extract from tirerack's website on camber settings, it pretty much supports what I said above:

The camber angle identifies how far the tire slants away from vertical when viewed directly from the front or back of the vehicle. Camber is expressed in degrees, and is said to be negative when the top of the tire tilts inward toward the center of the vehicle and positive when the top leans away from the center of the vehicle.



Since street suspensions cannot completely compensate for the outer tire tipping towards the outside when the vehicle leans in a corner, there isn't a magical camber setting that will allow the tires to remain vertical when traveling straight down the road (for more even wear), and remain perpendicular to the road during hard cornering (for more generous grip).

Different driving styles can also influence the desired camber angle as well. An enthusiastic driver who corners faster than a reserved driver will receive more cornering grip and longer tire life from a tire aligned with more negative camber. However with the aggressive negative camber, a reserved driver's lower cornering speeds would cause the inside edges of the tires to wear faster than the outside edges.

What's the downside to negative camber? Negative camber leans both tires on the axle towards the center of the vehicle. Each tire develops an equal and offsetting "camber thrust" force (the same principle that causes a motorcycle to turn when it leans) even when the vehicle is driven straight ahead. If the vehicle encounters a bump that only causes one tire to lose some of its grip, the other tire's negative camber will push the vehicle in the direction of the tire that lost grip. The vehicle may feel more "nervous" and become more susceptible to tramlining. Excessive camber will also reduce the available straight-line grip required for rapid acceleration and hard stops.

Appropriate camber settings that take into account the vehicle and driver's aggressiveness will help balance treadwear with cornering performance. For street-driven vehicles, this means that tire wear and handling requirements must be balanced according to the driver's needs. The goal is to use enough negative camber to provide good cornering performance while not requiring the tire to put too much of its load on the inner edge while traveling in a straight line. Less negative camber (until the tire is perpendicular to the road at zero camber) typically will reduce the cornering ability, but results in more even wear.

Even though they have some of the most refined suspensions in the world, the next time you see a head-on photo of a Formula 1 car or CART Champ Car set up for a road course, notice how much negative camber is dialed into the front wheels. While this is certainly an example of wear not being as important as grip, negative camber even helps these sophisticated racing cars corner better.

[Okan509]

lulz

[jaymac]

Front toe is now .13* D / .14* P / .26* Total; Rear toe is .12* D / .1* P / .22* Total. All those figures are in the "green" area on the printout. Sound OK?

[JamesRS5]

Sounds good, just keep an eye on the inside edge of the tires over the next month, if they look like they are starting to wear at a higher rate to the outside edge or the car feels uneasy especially in acceleration (where you will feel it the most) then the UCA's may be a worthy investment.

[Du Werke]

JamesRS5, I am fully aware of the definition of camber...

I ran -4.5 degrees in the rear of Porsche C4S in order to fit a 315/25/19

Mind you, that is about $1000 just in rear rubber.

With my toe set correctly, the tires looked nearly the same a year after mounting them and this included about 5k miles and three road trips later.

I currently run -3.8 on all four corners on my Audi and once again, with a proper toe alignment -- zero unusual wear 6 months and 10k miles later.

I could go on and on about how many times I've been around the block but here is the long and short of it:

If you run as you are at a nominal -2.5 for 30k miles, you will experience the same tread life as if you were zero'd as long as the rest of your alignment is in check

In more extreme cases, the outer edge might show less wear at the end of a tire's lifespan than the inside (coning), but that doesn't mean your tires wore out faster. In all my experience, tread life has remained the same however the outside edge wore at a slower rate.

[jaymac]

Good to know!
Thanks all for your input :)

[JamesRS5]

JamesRS5, I am fully aware of the definition of camber...

I ran -4.5 degrees in the rear of Porsche C4S in order to fit a 315/25/19

Was that done for cosmetic reasons?

Wider tires don't give you a larger contact area unless the weight of the car is increased or you lower the tire pressures - the contact patch between the tire and the road will remain exactly the same, it will just be a different shape (more rectangular then square but exactly the same surface area). Increase the camber angle and you have actually decreased the contact patch so your wider tires are now actually giving you less contact area with the road!
Seems crazy doesn't !?


Your last statement doesn't really make any sense or you are contradicting yourself? If the tire was at factory camber then the wear would be even across the tire, with increased negative camber the inside wears faster than the outside or as you said the outside wears slower than the inside edge, either way, a tire with excessive negative camber will wear faster than a correctly aligned tire.

I'm not here to argue or pick a fight so I won't reply to this thread again. I have some pretty sound experience in this field and I just want to share my knowledge in geometry. For the OP, just keep an eye on the front tires and hopefully all will be well but there's a reason the sensible guys with lowered cars run adjustable UCA's and I'll leave it at that.

[Du Werke]

Was that done for cosmetic reasons?

Yes. This was done in order to run a very aggressive set of wheels and tires. No other purpose.

Your last statement doesn't really make any sense or you are contradicting yourself? If the tire was at factory camber then the wear would be even across the tire, with increased negative camber the inside wears faster than the outside or as you said the outside wears slower than the inside edge, either way, a tire with excessive negative camber will wear faster than a correctly aligned tire.

no, I meant what I said. Lets say a particular tire on a particular car at zero camber would last 30k miles. Add subject B who ran negative camber but had all other alignment specs green: He too will last 30k miles, but at that 30k miles will notice slightly less wear on the outside edge than the rest of the tire that needs replacing. So no, I'm not contradicting myself. Either tire will need to be replaced at the same time, however tire B might look a little better on the outside when that time comes. I.E. "slower"

I have some pretty sound experience in this field

As do I, and sensible is a relative word.

[Hippyshakes]

Camber we all get along?






(sorry I had to)

[shonseb]

Lol

Sent from my Nexus 7 using Tapatalk

[Pworld]

Keep those toes in check and you will be fine. I ran those specs on a tire with horrible tread wear ratings and got about 25k out of my tires wear wise. Bubble wise was a different story (30 series). YMMV

[importraceram]

Encouraging news. I drive 400+ miles per week. Think my tires will last past Labor Day? [IMG][/IMG]

[Mops@Nemesis]

Being your car is riding on it top, your tires should last a veryyyyy long time

[importraceram]

Being your car is riding on it top, your tires should last a veryyyyy long time

Ha sorry for the upside down pic. You get the point though. Camber is...ehhh but toe is in check