t34418l31

Tire is a Hoosier R7 on a Miata running 4* camber. I'm having tire wear as shown below and I just wanted to get some opinions on why it is wearing as such. There is a stripe on the left 1/3 on the center section that exhibits the most amount of wear.

Left front tire (left is outside)
2400 lbs Miata
4* camber
38 psi

cosm3os

You are a bit high on your PSI and camber, according to Hoosier's literature. I'm assuming the inside of the tire is to the left of the picture.

t34418l31

Sorry forgot to add the left side is OUTSIDE of tire

Brian C in Az

You listed 4˚ of camber
Did you mean -4˚ of camber.
Negative is when the top of the tire is tilted in.
Positive is tilted out
Positive would explain the wear.

Presuming you meant negative 4˚, you did not list your toe.
There are several variables in alignment and suspension/steering set up that can cause or mimic camber wear; especially with a tire with no sipes to give more clues.
Excessive toe in or out is one of them.
38 psi - Hot or Cold?

Post a picture showing the top of the tire at a horizontal angle looking at the grooves.

That will show us if the tire is wearing flat or not.

gbuff

Not an expert but -4 is a boatload of camber--if anything the inside of the tire would show more wear, not the outside. As stated, I think you've got other issues at play here.

Gary

will968

Looks like an overworked tire from an understeering car.

Difool

mark kibort

yep and way way too much pressure.

mark kibort

the real question that im surprised no one asked, is what is your toe setting... too much toe in, only a little, can show this kind of wear too. especially the fact that you have 4 degrees camber (a lot) and you are still wearing outside 1/3rd.

gbuff

Post #4, Mark

Gary

mark kibort

well its such a great question, i thought i would ask it again. probably a likely suspect! nice work Gary!

t34418l31

toe out is 1/8" total measured at 24"

rears are -3.6* and show even wear

38 psi hot

mark kibort

24" front of contact point on tire, vs rear? so, if its toe'ed out, by 1/8", that a little much, but would show itselft by inside edge wear , not outside. your pressure can defintely be apart of it. optimal pressures by most of the spec miata guys are in the lower 30s. (32-34psi) that is substantial wear and its very surprising considering the high camber, but too high of spring rate, or compression, could also cause this