Wheel alignment settings

[Viren]

Hi all, new to the forum so go easy! The zmc is due a wheel alignment however wanted to get your thoughts on whether to stick with oem or reduce rear toe and increase front and rear camber (seems to be a good way to make the car more progressive and neutral). Car is a daily driver with a couple of track days a year so would be interested in tyre wear as well. Btw awesome forum! Cheers, Viren

[exdos]

After experimentation my preferred settings are zero toe all round and reduced rear camber.

[BMWZ4MC]

After experimentation my preferred settings are zero toe all round and reduced rear camber.

And increased front camber, or did you stick with OEM front camber settings John?

[exdos]

After experimentation my preferred settings are zero toe all round and reduced rear camber.

And increased front camber, or did you stick with OEM front camber settings John?

I tried increasing front camber by removing the pins after I'd done all my other suspension mods, but I found that, like with the Z3MC, it makes the handling far too twitchy on public roads and therefore tiring to drive, so I reverted to OEM front camber. If I had camber/caster plates, I would increase the caster a tad, which would increase the dynamic camber but also retain/increase straight-line stability.

[Viren]

Cheers guys, curious to understand how the driving dynamics change by reducing rear toe and camber? Also were bmw being conservative with they rear set up (eg induce understeer however making the car less progressive)

[Machine monkey]

I know this is the M specific area but dose any of this apply to non M zeds? I am looking at getting all my alignment set up shortly. I have a few suspension components still to replace but do i just go factory?

[exdos]

Cheers guys, curious to understand how the driving dynamics change by reducing rear toe and camber? Also were bmw being conservative with they rear set up (eg induce understeer however making the car less progressive)

The Z4M's OEM geometry does a good job of preventing the car from directing itself into the scenery (unlike it's predecessor- the Z3MC). The front geometry with a fair amount of toe-in creates understeer and the rear geometry, with a fair degree of -ve camber and toe-in reduces the tendency to oversteer and fish-tailing with excessive throttle input. All in all, the car has a tendency to understeer. Reducing rear camber and zero toe all round produces a more neutrally handling car. If your car has lowering springs, the the camber and toe will change.

I know this is the M specific area but dose any of this apply to non M zeds? I am looking at getting all my alignment set up shortly. I have a few suspension components still to replace but do i just go factory?

I don't know the OEM geometry of the non-Ms but changing the settings to what I have should also make a neutral handling car. Obviously, if anyone decides to change the geometry from OEM, they do so at their own risk.

[Viren]

The Z4M's OEM geometry does a good job of preventing the car from directing itself into the scenery (unlike it's predecessor- the Z3MC). The front geometry with a fair amount of toe-in creates understeer and the rear geometry, with a fair degree of -ve camber and toe-in reduces the tendency to oversteer and fish-tailing with excessive throttle input. All in all, the car has a tendency to understeer. Reducing rear camber and zero toe all round produces a more neutrally handling car. If your car has lowering springs, the the camber and toe will change.

Thanks, really useful info. What camber and toe numbers are you currently running (guess toe is close to 0 given your previous comment), cheers

[exdos]

Thanks, really useful info. What camber and toe numbers are you currently running (guess toe is close to 0 given your previous comment), cheers

I run OEM front camber and approx -1.2 rear camber. Zero toe all round. I use this both for road and at The Ring. I must qualify to say that I also have AC Schnitzer Racing (adjustable suspension) H&R CSL ARBs, RTAB Limiter kit and 10mm wheel spacers all round, but I still think my geometry will apply with OEM suspension.

[BMWZ4MC]

After experimentation my preferred settings are zero toe all round and reduced rear camber.

And increased front camber, or did you stick with OEM front camber settings John?

I tried increasing front camber by removing the pins after I'd done all my other suspension mods, but I found that, like with the Z3MC, it makes the handling far too twitchy on public roads and therefore tiring to drive, so I reverted to OEM front camber. If I had camber/caster plates, I would increase the caster a tad, which would increase the dynamic camber but also retain/increase straight-line stability.

I'm looking forward to experimenting with mine once I've fitted everything. I'll likely be running as much negative camber as possible on the track but I do agree it makes for a very twitchy ride on poorly maintained roads. Fortunately, I have camber/caster plates

[Vanne]

Hi exodus,

Getting my h&r lowering springs with my new blistein hd's installed tomorrow, what settings would you recommend for this setup? I realize the new springs will need to bed in for about 500kms. Any insights to the setting if I use a 10mill spacer for the fronts and 3mill for the rear?

[exdos]

Hi exodus,

Getting my h&r lowering springs with my new blistein hd's installed tomorrow, what settings would you recommend for this setup? I realize the new springs will need to bed in for about 500kms. Any insights to the setting if I use a 10mill spacer for the fronts and 3mill for the rear?

Vanne,

If you are using lowering springs, this automatically increases -ve camber, and at the same time it changes the toe angles. Personally, I would get the toe angles set at zero (or very slight toe-in) and reduce the rear camber to about -1.2 degs.

The whole concept of setting static geometry is to optimise the car's handling and tyre contact patch in the dynamic situation. The geometry settings always will be a compromise which attempts to account for the changes in damper length (ride height), pitch, squat and lateral bodyroll, all of which change the car's handling and tyre contact patch dependent on the attitude of the car in the dynamic situation. You'll find the front toe angle has the biggest effect on the perceived handling of your car.

I know that lots of negative camber on the front wheels looks cool, but unless you get the same degree of bodyroll as the angle of -ve camber when hard cornering, then you aren't actually using the full width of the tyre in the contact patch, consequently the inners of the tyres tend to wear excessively, especially with some toe-in. If you can reduce bodyroll with better suspension then IMO, there's less need for increasing -ve camber. I hope this makes sense to you.

[FR08MEE]

Hi exodus,

Getting my h&r lowering springs with my new blistein hd's installed tomorrow, what settings would you recommend for this setup? I realize the new springs will need to bed in for about 500kms. Any insights to the setting if I use a 10mill spacer for the fronts and 3mill for the rear?

Vanne,

If you are using lowering springs, this automatically increases -ve camber, and at the same time it changes the toe angles. Personally, I would get the toe angles set at zero (or very slight toe-in) and reduce the rear camber to about -1.2 degs.

The whole concept of setting static geometry is to optimise the car's handling and tyre contact patch in the dynamic situation. The geometry settings always will be a compromise which attempts to account for the changes in damper length (ride height), pitch, squat and lateral bodyroll, all of which change the car's handling and tyre contact patch dependent on the attitude of the car in the dynamic situation. You'll find the front toe angle has the biggest effect on the perceived handling of your car.

I know that lots of negative camber on the front wheels looks cool, but unless you get the same degree of bodyroll as the angle of -ve camber when hard cornering, then you aren't actually using the full width of the tyre in the contact patch, consequently the inners of the tyres tend to wear excessively, especially with some toe-in. If you can reduce bodyroll with better suspension then IMO, there's less need for increasing -ve camber. I hope this makes sense to you.

Regarding the tyre wear i have set my front -ve camber to maximum negative camber with the pins pulled (approx 1.2-1.3 degrees i believe... possibly more with 0 toe) and the tyre wear across the front tyres is now even where it wasn't before.

Although my allignment was pretty far out i believe that adding negative camber on the front of an M (within reason) actually improves the tyre wear on the inside of the front tyres (same applies to an E46 M3) although this may also be down to changing the toe to 0/ a combination of both.

The wheel allignment i had certainly had a big impact on my car and would highly recommend getting it done regularly especially considering its a relatively small outlay. I should also mention my car is completely standard in terms of suspension.

[exdos]

Although my allignment was pretty far out i believe that adding negative camber on the front of an M (within reason) actually improves the tyre wear on the inside of the front tyres (same applies to an E46 M3) although this may also be down to changing the toe to 0/ a combination of both.

It's toe that scrubs the tyres far more than camber, because the wheels are not rotating in the direction of movement of the car unless toe is at zero.

[Viren]

So here's what I'm thinking:

Front camber: 1.0
Front toe: close to zero or slight toe in (0.04)

Rear camber: 1.4
Rear toe: 0.06 toe in

Given the car is used daily, mostly road use, couple track days a year seems an okay compromise. Any thoughts?