TL;DR

  • Start from the factory values. Bentley’s E36 alignment tables, below, are the baseline for a road car, including the sport-suspension and M3 versions.
  • Lowering changes the geometry: mainly more negative rear camber, plus a changed toe curve at the front. Correct it with the right parts rather than living with tyre wear.
  • Tools for correction: front camber plates or offset control-arm bushings, and adjustable rear arms. Any change ends with a four-wheel alignment.

What the angles do

  • Camber: the wheel’s lean in or out at the top. More negative camber gives more grip in corners, but wears the inner tyre edge on the road.
  • Caster: how far the steering axis leans back. More positive caster means stronger self-centring and stability, and heavier steering.
  • Toe: whether the fronts of the wheels point in or out. Small changes have a big effect on stability, turn-in and tyre wear.
Camber, caster and toe Camber, seen from the front: negative camber means the top of the wheel leans in towards the car. Caster, seen from the side: positive caster means the steering axis leans back at the top. Toe, seen from above: toe-in means the fronts of the wheels point slightly towards each other. Camber front view negative: top leans in car centre is to the right → Caster side view positive: steering axis leans back at the top ← front of car Toe top view front ↑ toe-in: fronts point slightly inwards
What the three alignment angles describe. Angles exaggerated for clarity; the factory values are in the tables below.

Factory alignment specifications (Bentley)

Front

318i / 325i318i / 325i sport suspensionM3 3.0M3 3.2
Toe (total)0°18′ ± 8′0°18′ ± 8′0°10′ ± 5′0°10′ ± 5′
Camber, to 1995−0°40′ ± 30′−0°58′ ± 30′−0°55′ ± 30′—
Camber, 1995 on−0°30′ ± 30′−0°51′ ± 30′−0°55′ ± 30′−0°46′ ± 30′
Caster (at 10° wheel lock)3°41′ ± 30′3°50′ ± 30′6°38′ ± 30′9°35′ ± 30′

Rear

318i / 325i318i / 325i sport suspensionM3 3.0M3 3.2
Toe (total)0°24′ ± 6′0°24′ ± 6′0°30′ ± 6′0°30′ ± 6′
Camber−1°40′ ± 15′−2°0′ ± 15′−1°45′ ± 10′−1°45′ ± 10′

Note how the M3s run far more caster than a standard 318i or 325i. That’s why M3 parts are a popular way to add caster to other E36s.

Front: camber and caster

  • Camber plates replace the upper strut mounts and allow front camber (and on some designs caster) to be adjusted. Check the plate’s design suits your struts and any coilovers.
  • M3-style offset control arm bushings move the control arm’s rear mounting point and add caster. The BMW bushing 31 12 9 069 035 is listed on RealOEM for the 1995–1999 E36 and the Z3; confirm the fitment for your car.

Rear: camber and toe on a lowered car

As the rear goes lower, the wheels gain negative camber. On a lowered car it can end up beyond the factory range, which wears tyres and upsets the balance. Adjustable rear arms (camber and toe) allow it to be brought back. When fitting them, set them up so that the factory-style adjustment is used sensibly, then have the car aligned. Tighten rubber-bushed arms at normal ride height. Control arms to the trailing arm are 110 Nm and to the final drive carrier 77 Nm (Bentley).

Bump steer and roll centre

Lowering a strut-suspended car changes the angle of the control arms and tie rods. The car may steer itself over bumps (bump steer), and the roll behaviour changes. Specialist parts exist to correct this on heavily lowered track cars. For a moderately lowered road car, a correct alignment and suitable dampers matter far more.

Getting the alignment right

  • Use a shop with modern four-wheel alignment equipment, and ask for the before-and-after printout.
  • Bring the car at its normal ride height and load, with tyre pressures set.
  • After any suspension work (bushings, arms, steering rack, ride height), align again.

See also: suspension refresh, steering rack swap.