[Will_460cs]

Hi,

I thought this may help a couple of people, here are my calculations and alignment specifications for a string alignment of a E91 (E90,E92 should be the same as well)..

18" wheel = 458mm Across face to rim edges

Front Axle
BMW Specification is total toe 0° 14'
So, 7 minutes per wheel
0.11667 degrees
= 0.93mm Toe in

Camber 0° 33'
So 0.55°

Rear Axle

Total Toe . 0° 18'
So, 9 minutes per wheel
0.15 Degrees
=1.2mm Toe in

BMW specification: camber 0°50'
= 1.83°

[Will_460cs]

Here are some pictures

[Will_460cs]

Equipment used

Ramps
Steering Plates
Steering wheel lock
2 x 2M x15mm long Aluminium poles ( got mine from a local company that make light rigging and other Aluminium stuff..)
2 x Water Pipe Cladding
.5mm mono filament fishing real (this stuff made all the difference when it comes to accuracy)
Vernier calliper (or a steel rule, I'm probably too obsessive about detail!)
Plastic Tube 3m long (to set a water level for wooden blocks)
Offcuts of Sleepers and wooden blocks to create a level
Laminate flooring + grease (2 pieces in plastic bag with grease in the middle to act rear slipper plates)
Bungee straps (to hold the poles)

Spanners etc to adjust...

Camber:

Smart camber Gauge (or any other digital level that will measure of the edge of the rim)

[justpete]

Lots cheaper than Watkins SmartStrings, that's for sure.

[Will_460cs]

yes its cheaper than smart strings! but just as accurate and have used this method on lots of cars.. Caterhams, 996, Lotus Cup etc...

[Will_460cs]

Basic method (does not include getting it the air!)

Mark the aluminium poles so the you have equal distance on both poles - note the position of the blue masking tape and fishing line in the picture. It is very important to be accurate!

The fishing line should be positioned so that it goes through the centre point of the hub.

Measure from the wheel hub at the front (or cap if it not deformed!) with a good metal rule or Vernier so you have an equal distance

Rinse and repeat for the rear hubs

You now have a created a exact parallel square over the car which you can measure against.

I can go into more detail if wanted, but the pictures hopefully explain a lot.


Notes:

To ensure you have a level platform to work on use a length of clear tube - then fill with water to create a level.

Camber - Buy a digital level and measure from the rim face edges...

[tlow98]

Wow, nice little set up! Always wondered how this was done. You change actual settings via the cam lobe bolts?

You decide to add more front camber? I suspect you might have wanted to but not sure as you listed the BMW specs only..

[Will_460cs]

I set it this time round at BMW specs as it was someway adrift, the nice thing is that you can try things out and adjust.

A lot of people who have posted alignment data quote Total Toe as individual wheel Toe. I've seen a few alignments that are done this way (so 14' and and 18' minutes per wheel) my car was set up this way and tyre wear was terrible.

This is my daily so Im not trying turn in it a track best, but a good road car.

[Will_460cs]

Originally Posted by tlow98

Wow, nice little set up! Always wondered how this was done. You change actual settings via the cam lobe bolts?

You decide to add more front camber? I suspect you might have wanted to but not sure as you listed the BMW specs only..

On the rear there are 2 eccentric bolts for camber and toe - yes thats the method for changing the rear...

[Will_460cs]

this the steering wheel clamp:

http://www.ebay.co.uk/itm/QuickTrak-...0AAOSwA3dYLEm8

These are the turn plates:

http://www.ebay.co.uk/itm/QuickTrak-...AAAOSwARZXld~-

Well done OP

I keep telling myself that one of these days I'll get proper length poles myself given that lining up jack stands every time is much more of a pain.

[Will_460cs]

Thanks! Poles make it a lot easier especially when attached to the car. I got mine from a company that makes lighting rigging locally for £10! they are 2m long by about 20/25mm.

I highly recommend the use of sleeper offcuts to raise the car as well, it works better than ramps and allows you to settle the car more.

I'll be purchasing another sleeper just to cut up for this purpose....Until I have a garage big enough for a ramp.

This is definitely a very rewarding job to do yourself (and easier with a mate! but not a grumpy GF)