BMW 130i manual wheel alignment

[gofaster 12]

Hi. Not sure if this is the right thread but here goes.

My 130i is going in for a wheel alignment tomorrow.

Will get mostly daily use with the odd sealed Autocross thrown in.

Can you alter the alignment in these cars (camber, castor etc) to help with the odd Autocross or should I just ask for standard settings?

Am running standard 17" rim's with potenza RE003's all around 205 on front 225 on rear.

Cheers, John.

[M3AN 3330]

13 hours ago, gofaster said:

Can you alter the alignment in these cars (camber, castor etc) to help with the odd Autocross or should I just ask for standard settings?

There are some minor adjustments you can make:

Research the "camber pin mod" and do that before your alignment and then ask for as much front camber as can be achieved so that it's equal on both sides. Advise them that it can be adjusted at the top of the strut (because you've just removed the camber pins which allows for an extra half of a degree of camber). You should end up with about 1 degree of negative camber up front.

If you ask for a small amount of toe out at the front you'll gain sharper turn-in and mid-corner traction at the expense of directional stability. Around -0.5mm (I run -0.6mm) will be fine. Needs to be even on both sides. That's not BMW spec which is toe in for pottering around town.

Compensate for the (tiny) loss of directional stability up front by going a little toe in at the rear, again no more than about +0.5mm. BMW spec is quite timid here too, they're expecting nearly +1mm of rear toe which is unnecessary unless you want to drive with your hands off the wheel.

Max rear camber, even on both sides. There's not a lot of adjustability here and you can't go too far.

Castor is factor of all of the above and can't be adjusted independently. 

You want a resulting "thrust angle" of 0 degrees or as close to it as possible (mine is 0*01' - 1/60th of a degree - so effectively zero).

Make sure you get the printout to take home.

Edited December 20, 2020 by M3AN

[gofaster 12]

Thanks Dave.

Had a go at the Camber pin mod this afternoon.

Looks a bit rough but job done, can now utilise the slots (I know why I am not a mechanic)

Will pass on your figures to the alignment shop, see what he can do, and of course will get a print out for reference.

Will start another thread for all the jobs I have lined up over Xmas and New Year.

 

[gofaster 12]

Got the alignment done

here is the printout.

Bit wet today so could not test out how it feels.

[M3AN 3330]

47 minutes ago, gofaster said:

Got the alignment done

here is the printout.

Bit wet today so could not test out how it feels.

Ace. Let us know how you get on when it dries up!

[gofaster 12]

Will do, although I only fitted the RE003's a few days before the alignment so not a true single comparison from when the runflats were on.

[3pedals 1037]

Rear toe looks shiite , not enough and too different - should be closer e.g  0.6 - 0.8 both sides 

 and contrary to what Dave says Toe out does not provide faster turn in  it just makes the inner wheel grab more and when combined  with negative camber, is a bad combo - it just scrubs the inner shoulder off when you are driving straight  and then rips it off when turning. 

if you want to run less toe then you should run less negative camber. 

It was a 1980's  trick to get shitty cars running positive camber to turn in  

[3pedals 1037]

Here is a simple analogy for you:

Put yourself in downward facing dog  ( Adho mukha svanasana)  with your thumb and index finger  making a 'V''  in front of you - index finger pointing out at 30 degrees from straight ahead and hands shoulder width apart. - Notice where the weight falls on your hands 

Now move your hands out wider than shoulder width and notice that the weight increases on the inside of your hand ( this is toe out negative camber) 

Now turn your hands inwards until the weight is even across the palm and pads of your hand - this is correct alignment ( negative camber toe in) 

Turn your hands in further and the weight transfers to the outside of your hands ( too much toe in ) 

Move your hands wider apart and the balance comes back to across the hand - this is now correct camber for the increased toe in 

For the toe out correct camber--  move your hands closer together with the initial hand alignment - ( outwards by 30 degrees) notice how the weight is even when your hands are narrower than shoulder width - positive camber toe out. 

Namaste 

Edited December 25, 2020 by 3pedals

[Jacko 1314]

Instructions unclear. Popped disk, shat pants. 

[3pedals 1037]

search for a video and try again - most common pose in Yoga