Im having a bit of a problem with tyre wear. Only my very outside shoulders of the front tyres are scrubbing out heaps. To the point that, although the rear tyres were only put on the front less than 5000km ago, the tyre is a bit above the tyre wear indicator, however just the outside shoulders are basically competely smooth.

I have been running around 40 psi + to try and compensate for this, but it still hapenning. My alignment wasnt too bad before, and since doign suspension work, the front have about 0.4 degrees of negative camber at the front.

Was wondering what type of camber you guys were running, and how bad your tyre wear is. I guess I corner pretty hard, but maybe I need to up the negative camber a bit??? There is a little bit of toe in, 2.4mm from memory, so that cant be the problem either..

Any numbers or advice would be appreciated. By the way I am running 245/40 18's Kumho Ecsta Supra tyres with new KYB shocks, King lows and whiteline rear sway bar, with some custom alignment settings.

Cheers,

Ollie

If its wearing outside of the fronts its a toe issue...

If its wearing outside of the fronts its a toe issue...

I would have thought so too, but before when I got my suspension work done they actually said there was a fair bit of outside toe.... And as per my post, the toe in was set to only 1.2mm each side. And I really trust their work.

Also, the outside wear seemed fine when I got the car, even though the tyres had a fair bit of mileage. However my driving seems to have made it pretty bad.

Im thinking I need some more neg camber. Also not sure about castor, apparently addign more castor changes the camber when the wheels are turned, sounds like this would be good for me??? Dunno if castor is adjustable, maybe you can get castor bolts or something. I know they put some camber bolts it when the suspension work was done.

Ollie

Hard driving will take off the outside edges. The only cure is to lessen the toe. If you tell them that you drive hard they should take this into account and reduce you toe to about zero. Lots of negative camber is good for the track, but does more harm than good on the road

I was lead to believe the Camber, and Castor isnt adjustable on our Magnas, unless you get some after market gear such as whiteline (which offer limited settings), or full out adjustable strut tops

I was lead to believe the Camber, and Castor isnt adjustable on our Magnas, unless you get some after market gear such as whiteline (which offer limited settings), or full out adjustable strut tops

That's correct.

I've run -2 deg negative camber at the front for ages without any noticeably uneven tyre wear. And no I don't drive my car very hard on the street often.

In my experience most of the time crap tyre wear is caused my issues with toe, not negative camber (unless its massive). As long as there's no issue with toe, 1.5-2 deg negative camber seems fine for the street (yes it will probably wear slightly unevenly, but pretty much negligibly.)

If you wanto have some adjustability of geometry, whiteline gear is ok. Their bolt kit seems to be adjustable up to around 1.5-2 deg negative camber, and the offset castor bush (comes in the anti-lift kit) adds 1 deg of castor. Nice little mods, even if you don't drive it very hard often. Together with the whiteline rear swaybar they give noticeably sharper turn-in and better steering feel.

Personally, I am going to adjustable strut tops as -2 deg camber just doesn't cut it on the track, especially with R-compound tyres (semis) and street-oriented suspension.

I suspect I will settle on around -3 deg camber at the front, and that will be with MUCH higher springrates than King Lows sort of stuff (i.e around 2x).


Lots of negative camber is good for the track, but does more harm than good on the road

Agreed, though some negative camber is nice even for just street driving. IMO -1.5deg camber is a good compromise for the street, won't muck up your tyre wear to any noticeable extent, and will make the front end feel a little sharper.

Agreed, though some negative camber is nice even for just street driving. IMO -1.5deg camber is a good compromise for the street, won't muck up your tyre wear to any noticeable extent, and will make the front end feel a little sharper.


I personally only run around 1 deg negative with the whitline setup and it holds on really well(the 19" dunlops are alittle pricey to risk scuubbing). Also there is only one wheelaligner I trust with my car - ME :bowrofl:

hmm, I guess I could put a little more camber on since im only half a degree, and can do this since there are camber bolts in there. However it sounds like its not gonna do much. Does 1.2mm toe in each side for 2.4mm total sound like a lot? I wouldnt have thought that would be causing any wear, especially as there was more than double the toe out previously.

I guess it might just be the 2nd gen suspension design and the tyres I have on there :confused: I guess I'll just keep the tyre pressures up and try not to corner too hard.

Ollie

2 deg negatie is way too much for street use. I used to run that amount in my track car!

My KR, about .5 each side negative.

If you are running any negative then the only cause can be your toe. 2.4mm on wide tyres with lowering is WAY too much. You need to back this right off. With a degree of negative camber and this much toe under heavy brakes it would be like braking on ice skates. Also being FWD you have to compensate for front end movement under acceleration.

When you lowered, did you reset your rear lower control arm bushes?

back it off to zero toe to start with and see how that goes, I think in my KR from memory I used about 0 toe and my tyres were 100% even wear.

I have no idea about reseting the lower control arm bushes, however the place that did it are pretty good and probably would have done it. What would the difference be if they didn't???

The tyres actually seemed to be wearing pretty good to start with, but ive been throwing it around some corners recentyl and the tyres SEEMS to have worn accordingly, so I thought it would be more to do with cornering than some toe in wear occuring all the time.

My steering was so much better after, I think the toe out was causing some issues, tracking a lot more than currently, and felt a bit loose and wandery, so I wasnt too keen on reducign the toe in.

Im due for some tyres really, although they still grip very well the back tyres which were previsouly on the front are competely smooth on the shoulders, so when i get somem tyres I might get them to set the toe to close to zero. I thought 1.2mm each side seemed pretty minimal, but got no idea how it compares. Pity, alignment cost about $75 where i went :confused:

Ollie

Well if it has changed since the job was done then I can 99% say that they did not reset the bushes.

The lower bushes are solid units, if you lower the car, the lower arms are then at a different angle and the bushes will then slog out. This can cause the issues you have having.

What do you mean its changed since the job was done? If you are referring to wheel alignment, the only time its been done is immediately before lowering, and straight after lowering...

Ollie

When you lower the car, the lower control arms will be at a different angle in relation to the body. For this reason they need to have the nut that holds them to the control arm lossened, the car put on the ground and then re torqued.

If this is not done, they will tear themselves to bits in little time.

It is a thing that is rarely done and a cause of a lot of allignment issues in these and many other cars.

OK, so your suggesting that maybe this wasnt done and the lower control arm bushes have worn a bit and this wear had altered the alignment???

I might give them a call and ask if they usually do that, along with a price for some tyres and wheel alignment :confused:

Ollie

If you corner hard often, then IMO the camber you run is not enough, i'd try to bump it up to 1-1.5 negative and see how that goes, a street tyre generally won't generate enough grip to need much more camber than that, 2 degrees is already pushing it on the road using good grippy rubber, and you will notice exessive wear on the inside if not cornered hard. I'd try the 1.5 and see what happens.

You said you had 2.4mm of toe out? if i remeber correctly that should be wearing the inside edges of your tyre, not the outside, i could be wrong though.

The castor does indeed affect camber as you turn, the more leant back the strut is, the more the camber of your wheels will increase when they are turned, yet you don't get the negative drawbacks of uneven tyre wear or decreased straight line contact patch that exessive camber angles cause. The drawback of big castor angles is heavier steering/ more strain on the steering system, so you need to achieve the best combination of castor and camber to suit your driving style and budget, no point spending thousands on adjustable suspension if the only thing you are trying to do is make a middle of the range set of tyres last a few thousand kays extra.

Thanks, might crank a bit more camber at the same time. I thought castor was a standard adjsutment but seems you need some aftermarket goodies to adjust it so probably wont go down that route although it sounds like it would help a bit.

As for the toe in/out, before I got the car lowered it had excessive toe out, cant remember how much, but after it was lowered it was set to 1.2mm toe in each side, for a total of 2.4mm.

I thought the tyres were holding up a lot better after lowering but after looking at it recently seems its just as bad.

Ollie

My input in brief :)

I've been just recently looking in to camber and toe issues. Shall provide full report at later stage....

2.4 mm toe-in is on the given limit, I'd take it closer to 0 too.

Keep street camber close to given specs, ~ 1deg F and R.

Your tyre, if it doesn't have firm sidewall, it might give a bit and cause minor "bending under" and add to the wear during hard cornering. Pressures?
U do tyre "rotation", eh?

And last - from now on, ME too, will be the only person doing alignments - we finally deviced reliable tools to do these and discovered ~-4 deg at rear, even tho Pedders claimed it was "near 0 and ok?. This explains why the previous tyres wore badly on the inside. Been experimenting with some spacers and getting there.

Whiteline sells new, longer bracket bolts and spacers for rear and bolts for the front camber. No adjusting bolts for rear, I enquired and was surprised, cos the website claims different as part KCA 357 :nuts: .

Your tyre, if it doesn't have firm sidewall, it might give a bit and cause minor "bending under" and add to the wear during hard cornering. Pressures?
U do tyre "rotation", eh?


Good point, although they are pretty low profile tyres, apparently they have a much smoother ride than the previous falken tyres on there, so maybe they have a soft sidewall, and dont like heavy cornering. I supposed the huge increase in road holding since the new suspension was put on would only make this worse.

At first i was running around 36 psi, but since lowering they have been over 40psi. One thing I was thinking though, is that the toe in cant be a big cause of the problem, as there was more toe out before, and there was not excessive inside wear. It was a bit worn, but this may also have been due to too lower pressures before I got the car, and certainly nowhere near as worn as the outsides.

So I think your right, although adusting the camber and toe will help, I think the main problem is the tyres. I guess I should go for a tyre with a firmer sidewall this time, although this will obvisouly mean a harsh ride and noise, so its either that or put up with fast wear :confused:

Ollie

Ollie

Remember the 17's run far higher pressure than std, I used to run about 45 in mine.

The Falken are a great tyre but I tended to Kuhmo as they are sensational. They wear fast but are soft and grip like hell.

I think you should get back closer to 0 toe, given is a lowered FWD. The rear is not adjustale in wagons and second gen sedans