toe & camber kits ~ vs rolling resistance

[j12piprius]

I jacked up the car and looked at the tires today.

Both of the back tires have a large negative camber. The left tire has about an inch of tread on the outside that is hardly worn, and the inside of the tread sets down while the outside is still a 1/4 to 1/2 inch in the air. The right tire has about a 1/2 inch on the outside of the tread that is hardly worn, and the inside sets down while the outside is still more than a 1/4 inch in the air.

The front driver side tire has a positive camber, about a 1/4 inch of the inside tread is hardly worn, and the outside of the tread sets down slightly before the inside of the tread. The front passenger tread is evenly worn, and the tread sets down evenly. The front wheels are not nearly as bad as the back.

When a wheel is set up to have some camber angle, the ... tendency to turn increases the rolling resistance as well as increasing tire wear. A small degree of toe (toe-out for negative camber, toe-in for positive camber) will cancel this turning tendency, reducing wear and rolling resistance.

My impression from this quote is that there is not enough toe out in the back tires to cancel out the large amount of negative camber, and the front driver side tire doesn't have enough toe in to cancel the positive camber. However, if the camber in the back is corrected with a camber kit, then the toe wouldn't need to be adjusted as much to compensate, which is a better solution. I'm looking forward to getting a camber kit and then adjusting the toe, to increase the tire wear and reduce the rolling resistance.

I'm interested in your comments about adjusting the toe and camber in your cars.

[cbaber]

Is your suspension modified? Looking at your garage I don't see it listed, and the pictures look like your car is at the stock ride height. If you have a noticeable camber angle with stock suspension then you have some serious issues that probably need corrected before worrying about anything else. Have you had a shop check the alignment to get some #'s?

90% of the time, excessive wear is due to improper toe alignment or slop in the suspension (ball joints, bushings, etc. that cause toe issues while driving). The extra rolling resistance from a -2 degree camber angle is probably insignificant in terms of fuel economy, and it's not likely to cause wear issues if you rotate your tires frequently.

I wouldn't trust the average alignment tech to figure out how much toe is required to balance out the effects of the camber angle on steering force.

[kennybobby]

Check for the use of any rubber in the suspension linkages and mounting components, such as bushings, inserts or collars. The top of the rear suspension (strut?) may be rubber-mounted to the body, and old or worn rubber has sagged and let the top mounts move inward and caused the neg. camber. Toe-in and camber will wear out a tire quickly; the rear end of a front-wheel drive should be tracking straight ahead with no toe-in and no camber. i have built up a kit to do my own alignment on numerous vehicles over the years using basic tools: level, square, jack stands, string, vernier calipers, tape measure, small metal ruler, metal plates, chalk, wooden spacer blocks, binoculars, etc. Just need a fairly flat and level slab of pavement somewhere to do the setup and take measurements, then use a little trig and a calculatus device to know what you got...

[Vman455]

Originally Posted by johnlvs2run

I jacked up the car and looked at the tires today.

Both of the back tires have a large negative camber. The left tire has about an inch of tread on the outside that is hardly worn, and the inside of the tread sets down while the outside is still a 1/4 to 1/2 inch in the air. The right tire has about a 1/2 inch on the outside of the tread that is hardly worn, and the inside sets down while the outside is still more than a 1/4 inch in the air.

First, you can't check camber with the car in the air, or by trying to see what point of the tire touches first as you drop it. Get a plumb line and a board and mark off degrees, or a couple of levels, or rig up something else so you can check the angle of the wheel while the car is sitting on the ground. Checking toe is as easy as two jack stands, some fishing line, and a ruler. If your suspension is stock, there isn't much you can do to adjust camber, but adjusting toe is simple (if it's anything like the 7th gen Civic, at least).

[j12piprius]

Cbaber, as far as I know the suspension has not been modified and the car is original height. I want to do the easier things myself, and might have a shop check the alignment after that. The car is not bouncy, and has relatively low miles, so maybe the struts are okay for awhile.

Kennybobby, I'm impressed with you doing your own alignment, will check your previous messages and do the things you've suggested.

Vman455, I'm looking forward to doing the things you've suggested. Thanks much for all the helpful comments.

[Cobb]

I lowered my insight and was running -3 degrees camber. I also rotated my tires every 5 thousand miles, so after it was lowered I bet I was having less rolling resistance as both sets of tires were sitting on the edge of rubber vs the face or tread of the tire.

[Superfuelgero]

I wouldn't be worried about camber. Of course its visually off, theres a high chance the toe is off.

[Cobb]

Yes, lowering screws up the toe and other adjustments. The insight mentions a zero toe and it seems that aids in better mpg, but you are more suspect to windy days pushing you around.

[Superfuelgero]

Originally Posted by Cobb

Yes, lowering screws up the toe and other adjustments. The insight mentions a zero toe and it seems that aids in better mpg, but you are more suspect to windy days pushing you around.

More than 5 mpg according to car and driver. I picked up 4 on the VX using these settings, and 2.5 on the corolla.

[redneck]

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Checking Toe

The tire needs to be setting on level ground with the full weight of the car on all tires (suspension loaded). A tape ruler is all that is needed. Make sure the steering is pointed straight ahead. Hook one end of the tape in a tire groove on the front side of the tire and record the distance to the corresponding groove on the other tire, then repeat for the backside. The difference being the amount of toe. Another way (better) is to take two strings and tie either sinkers or large nuts to each end and drape the string with weights over the tire in a tire groove. Adjust the length of the string so that the weights are a inch or two above the ground front and back. Do the same for the other tire. Measure the distance between the front strings, then rear strings of the tires and record. This is better because the full diameter of the tire(distance between front and rear of the tire) will be accounted for. When using the first method, just the lower (smaller) radius is available to be measured because of the chassis being in the way. The first method however will tell you quickly whether or not you have a problem, just not as accurate. If it is a front wheel drive car you will also need to check rear wheel toe also . Just as important though is to check "thrust". Thrust is the difference between front and rear wheel (axle) alignment. Front and rear should be parallel. 0 degrees thrust. It is however more difficult to check by oneself.

Most shops charge around $70 for a 4 wheel alignment (laser). A bargain, considering the cost of fuel and tires these days as improper wheel alignment can cost you plenty. They can also tell if you have bigger problems, like worn out components.

I just had mine done and told them to set it up as,

Front - 0 degrees toe

Rear - 0 degrees toe

Thrust - 0 degrees

Caster and camber were within factory specs.







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