[Tambohamilton]

Joke! It's always toe.

Just forking this off another thread so I don't continue to hijack it:
https://www.e90post.com/forums/showthread.php?t=1920735

TL;DR is that I want to minimise front tyre wear while running significantly more negative camber than stock. Biginboca suggested 1/16-1/8" total toe in, which works well for him with -3.5deg camber.

I've now done that on my car, which has -1.8deg and was getting terrible inner edge wear with stock toe. It seems to have halted the wear, after 500mi of driving, but the front end feels pretty twitchy on the highway. Still, better than £250 of tyres every 5000mi!

For a car that'll see track time, how about setting the toe to not wear tyres with the struts pushed to least neg camber, then when you head to the track set the struts to the ideal (maximum) neg camber. This will decrease toe slightly for track use.

I also mentioned some info about toe/camber equivalence, but I think I was just remembering the approximation of 1deg of neg camber giving equivalent thrust as 0.1deg of toe.

[Biginboca]

I agree that toe is the first place where your attention needs to be for front tire wear.

Source of twitchy on highway could be a couple things…

Too much negative toe (not in this case, although maybe more toe would help)

If the car is lowered more than 1” it could be getting into bump steer (need drop tie rod ends like SPL or Turner)

Too much tire pressure (could try lowering a bit)

Oversized (wider) front tires tend to tram line which might feel twitchy

[feuer]

On street I run front -2.5 camber 0.0 toe rear -2.0 camber 0.5 toe out and only get rear inner wear. Tires are 235/40-18 and 255/35-18. For track I push front camber to -4.0 don’t readjust toe a all. Read untouched. 255/35-18 with 275/35-18 Tire wear in rear is better with the wider tires. Wear and how far feel varies on tire size and wheel offset too, to some extent.

[Tambohamilton]

Biginboca All fair suggestions. I'm running max pressure as per the factory guidelines right now. I'm sure dropping it to min recommended would help. I'm not lowered that much; BMWP front springs, with XD top mounts and a 10mm thick camber plate.

feuer How is it possible you get no inner edge wear on the front tyres?? What tyres do you run? And what pressure? The inner edge wear on my PS4 is so pronounced!

[feuer]

Originally Posted by Tambohamilton

Biginboca All fair suggestions. I'm running max pressure as per the factory guidelines right now. I'm sure dropping it to min recommended would help. I'm not lowered that much; BMWP front springs, with XD top mounts and a 10mm thick camber plate.

feuer How is it possible you get no inner edge wear on the front tyres?? What tyres do you run? And what pressure? The inner edge wear on my PS4 is so pronounced!

Absolutely no inner tire wear on front. Tires are 235/40-18 Continental DWS I’ll post some photos.

[Tambohamilton]

Not that I don't believe you...I just don't understand how. What part of my setup could be causing the inner edge wear, if my geo numbers are all more conservative than yours? Or do you only drive corners somehow?

[Biginboca]

Originally Posted by Tambohamilton

Not that I don't believe you...I just don't understand how. What part of my setup could be causing the inner edge wear, if my geo numbers are all more conservative than yours? Or do you only drive corners somehow?

How many miles on your car and what is the condition of your control arm bushings?

[Tambohamilton]

Nearly 150k miles. All suspension (everything!) replaced in the last 20k miles. All front control arms and top mounts done within the last 10k miles, with TRW or lemforder parts. M3 parts where possible. Front struts are koni special active (I know, no longer my first choice), and about 20k miles.

Rear end is a similar story, except the Meyle ball joints like you used. M3 upper arms, ball jointed toe arms.

The shop I used for geo I trust, though I've now edited the front toe myself (string lines).

[335i54n]

from my experience anything more than -1 camber in front and -1.2 in rear will cause a noticeable inner wear for dd.

[Tambohamilton]

Originally Posted by 335i54n

from my experience anything more than -1 camber in front and -1.2 in rear will cause a noticeable inner wear for dd.

Matches my experience

[Shoooter_j]

Same here - as soon as I put in Dinan camber plates, my old PSS were toast over 1 summer, but prior, outlasted a set of rears and easily had another few seasons in them.

Moved from -1.3 deg with alignment pins pulled to -2.75 / -2.67 deg (L/R) with camber plates. New 245 PS4S up front are holding up well for now, but suspect I’ll have around 4 seasons use max vs 6 with less aggressive camber. M3 control arms up front as well that have about 40k miles on them. No track, just street use so definitely not cornering as hard as you track junkies and might be some of the reason as to not wear as evenly as you guys

Edit: Toe is 0.04 / 0.06 deg in (L/R)

For the rears, its -1.78 deg camber with 0.15 deg toe in, and get the usual inner tire wear as well.

[feuer]

Originally Posted by Tambohamilton

Not that I don't believe you...I just don't understand how. What part of my setup could be causing the inner edge wear, if my geo numbers are all more conservative than yours? Or do you only drive corners somehow?

Either something is wrong with your suspension or alignment isn’t done properly. Many alignment machines aren’t mentioned properly and readings are off. I bought these tired use last year. Here how they look after around 10-12k miles. Front is off the car. Rear still in the car.

[Tambohamilton]

To be honest, I'm chasing something loose in my suspension and I have a new front wheel bearing to put in the passenger side because the one that's there looks like it's spat out the seal. But I can't find any play in anything! And the clunk noise really sounds like it comes from the rear. It's been through an MOT in this condition with no advisories...

[335i54n]

these are mine, you can see the e9x rear has an issue under compression it likes the wear on the very inside. you can see I was trying to balance the wear but too much air cause center wear and too little cause too much accelerated Inner wear. to get better wear in the rear I think I need less than -1 in the rear

[Tambohamilton]

I'll post pics of mine soon.

My front looks like you rear inside edge.

[Biginboca]

Originally Posted by Tambohamilton

I'll post pics of mine soon.

My front looks like you rear inside edge.

Since I’m swapping wheels and tires on mine today I’ll post some pics of the wear I’m getting

[Tambohamilton]

Worst photo ever, but this is front LH:


This is 1000mi after giving it ~1/8" total toe in.

[Shoooter_j]

Not that it may make a significant impact, but what tire pressures are you folks running?

[Tambohamilton]

I'm running the max pressures as listed on the door sticker; 2.7f and 3.2r bar. I've previously run 2.4f (min recommended) and 2.5r (min recommended is 2.7)...though that was mainly before getting to -1.8deg front camber.

[335i54n]

you need more psi (48/32 is my start, check tire load specs 1st) and a front swaybar upgrade (if u dont already), even that on stock width fronts i was getting little too much rollover wear. the 255 in my pic got noticeable better wear with more contact patch and really help front sway work better.

[Biginboca]

Here’s my tires compared. Tires on top are PS4S with 7,000 miles on them and 4 track days. Never rotated them either. I run 35 psi on the street on all 4 tires and drop them 5 psi for track.

The top left is front and the top right is the rear, below each tire is a brand new just mounted on the same spec rim as what’s above it. Inner treads are all to the right side in their pictures.



So that’s 7000 miles on front -3.5 camber and 1/16 toe in on the top left and 7000 miles on rear -2.5 camber 1/8” toe in on the top right.

Tires are all 255/35r18 and the front rims are 18x9 and the rear rims are 18x10. Since it was mentioned I’ll say I’m on Yellow Performance Springs and E92M3 front and rear swaybars.

[Shoooter_j]

Nice even wear - track is definitely helping keep the outer shoulders in check to be in line with the inners.

Here’s my even crappier pics - will try and get a daytime pic with wheels turned instead soon. Running 40psi all around and am on B12 Prokit, stock sways. 245/35/19.

Not sure why the second pic is rotated upside down, but first pic is driver’s front, second pic is passenger front. Third pic is the day I got them and drove home from the tire shop. Approx 6k miles on these since IIRC.