Geometry settings for ZMC?
- Thread starter hamza
- Start date
Raify said:
Well this all came about from me fitting a new steering wheel that was off-centre by about 20 degrees to the right. I know for sure the wheel is fitted perfectly as there is only one way it can go on but I'm starting to have doubts about things now
I mean I expect some very slight difference between steering wheels but surely not that much?I've posted up the before readings too below. The left front and rear cambers were well out as you can see. My limited knowledge is running out here but hopefully someone can help me get to the bottom of this i.e. is it the steering wheel that caused the problem, worn bushes/suspension components or the geometry people are talking rubbish?
Raify said:
Cheers that was my next step!
Should have gone there in the first place!playalistic said:Raify said:
Cheers that was my next step!
Or pop into Purley Tyres (on the Tilehurst to Pangbourne road). Good bunch. Only charge for what they do. Could give a second opinion. We left the front camber on mine alone as it was with the tolerance - to do it they need to knock out a pin (or something) to allow adjustment; easier if you don't have a strut brace on the car.
PawnSacrifice said:playalistic said:Raify said:
Cheers that was my next step!
Or pop into Purley Tyres (on the Tilehurst to Pangbourne road). Good bunch. Only charge for what they do. Could give a second opinion. We left the front camber on mine alone as it was with the tolerance - to do it they need to knock out a pin (or something) to allow adjustment; easier if you don't have a strut brace on the car.
Cheers, do they have hunter equipment?
The 'Mininum' i.e. Towards Neutral tolerances on that hunter specification of Front Camber (the two values at the top left/right of each box) are MUCH more lenient then the BMW specification...
Camber:
BMW Front Spec: 0Deg 80' - 1Deg 20'
Hunter Front Spec: 0Deg 40' - 1Deg20'
The Total Toe looks Low on the front and High on the rear too compared to the values provided earlier... I think we need things clarifying a little more!
Camber:
BMW Front Spec: 0Deg 80' - 1Deg 20'
Hunter Front Spec: 0Deg 40' - 1Deg20'
The Total Toe looks Low on the front and High on the rear too compared to the values provided earlier... I think we need things clarifying a little more!
EdButler said:
I should go back there? I'm thinking of just taking it to wheels-in-motion instead and seeing if they can arm me with something solid to complain about?
Shipkiller
Veteran
The front Camber can be adjusted if the tech removes the camber pin on the top of the strut mount. These are installed so the automated machines can align the top of the struts when the drive train is mated to the chassis of the car during assembly. Many drivers remove these pins and push the struts inward to get more camber. You can get, on average, as much as -1.8' of camber this way.
Before anyone tells me that this increases front tire wear, yes it can in a lot of circumstances. But, if you do a lot of spirited driving in the twisties, then this will reduce front tire wear due to the nature of the McPherson Strut suspension. Your improper toe settings will wear tires out faster...
The more toe you have, the more stable the car is in a straight line but you also have more tire wear. Less toe, the car is very sensitive in a straight line. Not unrully or flightiey or unstable, just sensitive. I perfer a performance car to be this way.
Caster is not adjustable, and hence it is greyed out in your print out. My suspension is stock (with exception noted below) and the caster on my Coupe' is less than the BMW specifications, being set to 5.6. ..............Manufacturing differences I guess, but this has my steering feeling a little lighter than someone with more caster.
It has been said that if you have your car aligned to factory specs, and the car still pulls ever so slightly, you can dial that out with as SMALL (.01 or .02) toe correction on one wheel as long as the Total Toe is in spec. This takes a really good tech to do. Almost Voodoo science..
Someone also mentioned their steering wheel. The tech must always center the steering wheel FIRST before any adjustment is performed. Hence the reason the tech must also recalibrate the Steering Angle Sensor so your DSC does not go crazy after he/she is done with the alignment.
Remember total toe is algebraically additive.
Also take into considerations that the BMW Z4 and especially the ///M alignment specs are really set up for the old man or woman driving the car who just wants a good driving car for the weekend and not setup for the person that wants it the best it can be. eg, the BMW enthusiast.
Rear camber is adjustable.
----------------------------------------------------
Do you ever take your car to the track?
If so, the BMW alignment settings are wayyyy conservative.
Since I do track time, I have thrown out the BMW settings.
At first I pulled the camber pins and pushed the struts in as far as possible. This got me a front camber of -1.8 & -1.9. If you do this, you WILL have to have the car aligned again since this will change your toe. I did two track events this way. The car handled much better but still had some understeer. PUSH for you NASCAR fans.
Now I have installed the Turner Motor Sport E36 Camber kit. With the camber pins reinstalled my new camber settings are listed below.
Now the car is almost neutral and balanced on the track. It is also even better driving day in and day out. It is my daily driver.
Now with new, non-stock tires 235/40R18 and 265/35R18, these are my alignment settings:
Front Camber: -2.4
Front Toe: .01 and .01
Total Toe: .02
Rear Camber: -2.0 (This is the max you can adjust on the car. If you want more camber you need adjustable camber arms)
Rear Toe: .02 and .03
Total Toe: .05
Thrust Angle: 0
Before anyone tells me that this increases front tire wear, yes it can in a lot of circumstances. But, if you do a lot of spirited driving in the twisties, then this will reduce front tire wear due to the nature of the McPherson Strut suspension. Your improper toe settings will wear tires out faster...
The more toe you have, the more stable the car is in a straight line but you also have more tire wear. Less toe, the car is very sensitive in a straight line. Not unrully or flightiey or unstable, just sensitive. I perfer a performance car to be this way.
Caster is not adjustable, and hence it is greyed out in your print out. My suspension is stock (with exception noted below) and the caster on my Coupe' is less than the BMW specifications, being set to 5.6. ..............Manufacturing differences I guess, but this has my steering feeling a little lighter than someone with more caster.
It has been said that if you have your car aligned to factory specs, and the car still pulls ever so slightly, you can dial that out with as SMALL (.01 or .02) toe correction on one wheel as long as the Total Toe is in spec. This takes a really good tech to do. Almost Voodoo science..
Someone also mentioned their steering wheel. The tech must always center the steering wheel FIRST before any adjustment is performed. Hence the reason the tech must also recalibrate the Steering Angle Sensor so your DSC does not go crazy after he/she is done with the alignment.
Remember total toe is algebraically additive.
Also take into considerations that the BMW Z4 and especially the ///M alignment specs are really set up for the old man or woman driving the car who just wants a good driving car for the weekend and not setup for the person that wants it the best it can be. eg, the BMW enthusiast.
Rear camber is adjustable.
----------------------------------------------------
Do you ever take your car to the track?
If so, the BMW alignment settings are wayyyy conservative.
Since I do track time, I have thrown out the BMW settings.
At first I pulled the camber pins and pushed the struts in as far as possible. This got me a front camber of -1.8 & -1.9. If you do this, you WILL have to have the car aligned again since this will change your toe. I did two track events this way. The car handled much better but still had some understeer. PUSH for you NASCAR fans.
Now I have installed the Turner Motor Sport E36 Camber kit. With the camber pins reinstalled my new camber settings are listed below.
Now the car is almost neutral and balanced on the track. It is also even better driving day in and day out. It is my daily driver.
Now with new, non-stock tires 235/40R18 and 265/35R18, these are my alignment settings:
Front Camber: -2.4
Front Toe: .01 and .01
Total Toe: .02
Rear Camber: -2.0 (This is the max you can adjust on the car. If you want more camber you need adjustable camber arms)
Rear Toe: .02 and .03
Total Toe: .05
Thrust Angle: 0
Does having CSLs fitted effect the figures in anyway ?
My car feels really unstable and light at high speeds . I've had the wheels balanced which has sorted a small wobble , but still feels very unsafe at speed . I have heard a few owners complain of this .
I'm going to have a geo done soon using hunter alignment .
My car feels really unstable and light at high speeds . I've had the wheels balanced which has sorted a small wobble , but still feels very unsafe at speed . I have heard a few owners complain of this .
I'm going to have a geo done soon using hunter alignment .
Jamster1, consider having your rear trailing arm bushes checked as deterioration in them can cause the symptoms you're describing. It won't have anything to do with the CSL's. Depending on mileage it might be worth doing them anyway and it will need the alignment afterwards anyway. I'm on 40k miles just now and I'm going to have mine replaced to sharpen everything up again in the Spring.
I also recently replaced the front lower control arm bushes in an effort to cure vibration through the steering wheel at motorway speeds. The problem was cured and had the added bonus of sharpening up the steering feel. This was in spite of the fact that the bushes showed no obviously visible signs of deterioration.
I also recently replaced the front lower control arm bushes in an effort to cure vibration through the steering wheel at motorway speeds. The problem was cured and had the added bonus of sharpening up the steering feel. This was in spite of the fact that the bushes showed no obviously visible signs of deterioration.
