Alignment spec

[jimprw]

'Within spec' is a very broad range. For mostly street driven miles, you could try to reduce the negative camber and zero out the toe. (if you were sticking with P Zeros or other asymmetrical tire) The side to side rotation isn't going to help much with this condition and asymmetrical tires like the P zeros.

Switching to the directional SC2s will require you to remount/flip the tires to rotate now. At least you change the inside shoulder out and should see much more mileage with these tires. Just a little more cost to do the rotation now.

Remounting is a really good suggestion. Thanks! Current toe is 0.07 Left/ 0.06 Right

 

[Grant 302]

Remounting is a really good suggestion. Thanks! Current toe is 0.07 Left/ 0.06 Right

Is that degrees or inches? If that's degrees, then total toe is about 1/16". If that's inches, I'd still try to get it closer to 0.

 

[jimprw]

Degrees. Total toe indicated on the printout = 0.13 degrees.

 

[Grant 302]

That's about what they had rolling out of the factory. The toe setting is a trade off between high speed stability and tire wear. If you're okay with flipping and rotating to help manage the wear, then it probably makes sense to leave it.

 

[jimprw]

Yes, it sounds like I might have to live with this problem. But, what still sticks in my mind is that the inside rib wear I experienced with the alignment properly set according to factory specs looks just like the uneven wear you would expect if you put lowering springs on a stock vehicle and didn't install caster/camber plates. Its almost as if Ford put in the performance springs as part of the awesome Boss package but didn't address the tire wear potential that would happen by doing so. I just can't get past the idea that if the wheels are aligned properly there should be even wear.

I can live with the fact that sticky performance tires will only last 15k - 25K miles because of the trade off of traction with durability. What bugs me is that it is possible a car could be engineered in such a way that significantly uneven tire wear is normal if the car is properly set up.

 

[Grant 302]

Yes, it sounds like I might have to live with this problem. But, what still sticks in my mind is that the inside rib wear I experienced with the alignment properly set according to factory specs looks just like the uneven wear you would expect if you put lowering springs on a stock vehicle and didn't install caster/camber plates. Its almost as if Ford put in the performance springs as part of the awesome Boss package but didn't address the tire wear potential that would happen by doing so. I just can't get past the idea that if the wheels are aligned properly there should be even wear.

I can live with the fact that sticky performance tires will only last 15k - 25K miles because of the trade off of traction with durability. What bugs me is that it is possible a car could be engineered in such a way that significantly uneven tire wear is normal if the car is properly set up.

I think you're right to feel that way. You're pointing out one of the major issues with taking a relatively cheap platform and suspension system then making it handle relatively well. The compromises in our mac struts aren't going to work for every driver or driving style.

 

[boro92]

I think you're right to feel that way. You're pointing out one of the major issues with taking a relatively cheap platform and suspension system then making it handle relatively well. The compromises in our mac struts aren't going to work for every driver or driving style.

I'm with Grant.

I replace my tires annually--and my car is only driven 6 months out of a year. It's just a part of the reality!
Track time + over 3600lb weight and if one is running the stock toe in alignment up front, it is absolutely no surprise that uneven tire wear is the result.

I run 0 toe, and a very mild -2.2 camber. Even still, I flip my tires every other track day and they still only last 6 months!

 

[Hermes]

14,800 miles and the front Pirelli P Zeros are done. Had the alignment checked, and all parameters well within Boss specific spec...in fact, the alignment was very, very good in feel as well as technically in spec.
So, there appears to be no technical reason why the fronts wore so badly on the inside ribs.
I can understand with soft compound tires that even with reasonable non-track driving I shouldn't expect to get more than 15 - 20k out of them. What still baffles me is why they wear so unevenly in front when still aligned properly. BTW, the rears P Zeros wore evenly inside to outside tread.
I went with the BFG G Force Comp 2 as replacements. As they are directional, I really don't expect any more than 15K from these either, especially since I can't rotate them. But, considering the inside rib wear on both fronts P zeros was almost uniformly awful even with side to side rotation, I guess rotation really doesn't matter to the life of the tread.

I had the same problem except I was able to get 21k miles and 7 track days out of the Pirelli's. Just bought a set of BFG Sport Comp 2's and MM camber plates. I also had my alignment checked when I first noticed the uneven wear on the inside fronts. The factory spec for the Boss [LS is slightly different] is -0.95 deg camber but there is a tolerance of +/- 0.75 deg. Very loose tolerance, probably to make sure every car that runs off the line with a suspension with limited adjustability is 'in spec'. While the neg camber is great for handling, I'm convinced it contributed to the early demise of my Pirelli's.

I have some racer friends who all do their own alignments and one of them gave me his old toe plates and camber bar with bubble gauge. My plan is to adjust camber to -0.5 for the street then -1.8 for the track for now. Hope to go to an open track event later this year and take a pyrometer with me to find out how much negative camber works best for the track.

I think that Ford was aware that the stock camber settings would impact tire life, but since almost everything is a compromise and this car was designed for handling, they skewed the settings in favor of better handling. I agree with their decision, I just don't want to spend more money on street tires than I need to since this money could be better spent buying track time, track tires, brake pads, coilovers...

 

[boro92]

Call me crazy but nearly 15k miles on a set of tires for a sports car (let alone 21k) sounds AMAZING to me
I replace tires on an annual basis (ok fine, I do go to 8 or so track events per year), but driving a car of this nature comes with high consummable costs. That big V8 along with 3600lbs should have been reason enough to expect such a thing.

Same goes for pads, rotors, ball joints, tie rods, bushings, etc

 

[badasbullitt]

I concur with the Ford setup and was wondering for street driving would I be wrong to adjust the camber for better wear. I really do not want to jeopardize handling just to gain a few more miles. So my question is should I adjust it alone for street driving although I may do a track every now and then. The insides are pretty much gone with 19k on them and looked to be scalloped somewhat which explains the vibration I feel from time to time.

 

[Hermes]

Well after installing my MM camber plates this weekend and setting the suspension at 0 camber 0 toe and driving around for 2 days, I just set camber at -2 & 1/4 deg and I ended up with 1/16 " toe IN. Can't believe how nice the car drives. Definite improvement in steering response and turn in. Guess if I could afford a new set of tires every 6k miles, I would definitely leave it like this.

Going to dealer tomorrow to have them set car to -0.5 camber and 0 toe. My idea is to see how close their before measurement lines up with mine, then see how close my after measurement lines up with their after meas. when I get home.

 

[13Boss#3328]

I have a question about alignment change after a track weekend!

Here is my alignment before the track

My alignment after the track day

Look at the before column of the second picture, I was surprised to see what a track weekend can do to the toe angle!?

Is that to be expected or I am missing something here?

 

[JScheier]

rear camber and toe change? My opinion (free of charge, because opinions are like a_holes)....

Different day, different alignment head setup, different tech.

It's REALLY hard to get exactly the same alignment specs from day to day. How the car is sitting on the rack, how much fuel is in it, how hung over the tech was when he put the heads on the wheels... all of these simple things can lead to differences in specs from day to day.

Everything else is pretty darn close (from day 1 vs. day 2). I'd chalk it up to the items listed above.