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Aligning the B5 A4/S4

For anyone who hasn't been involved with aligning the A4 or it's quadra-link suspension, it's a bit of a tricky task. You have the 4 control arms on each side in the front and no actual camber adjustment points. The idea with the quadra-link setup is that the design creates a "virtual steering axis". It helps reduce torque steer and bump steer.

As I noted before, there are no individual camber adjustment point in the front of the car. There is however, adjustment to the entire camber setting in the front by sliding the engine cradle from left to right. What this does is even out your camber between both side in uniform increments. You subtract X degrees from one side and add X degrees to the other. This process requires you to remove the belly cover and then loosen 8 large bolts on the subframe:



Then once you have loosened these bolts, you are supposed to attach a special tool on to bolts 3 & 4.



This tools allows you to slowly push the engine cradle sideways in small increments. I ended up having the shop use a very large prybar. The desired result was achieved.

In terms on toe adjustment, unladen toe is adjusted by simply adjusting the lock nuts on the tie rods ends however, this car has a follow up toe value called "raised toe". In order to check for the "raised toe" you must install an adapter on the front suspension that will create a slight lift. This slight lift must be used when checking the unladen toe first. Once you have placed the unladen toe in spec while using the adapter (rough adjustment), you must then use the adapter to raise the suspension even higher (60mm) to see what the toe looks like during rebound instances. Your alignment software should be new enough to calcualte the difference between unladen toe and raised toe to see if it is within the factory spec (ie. 0.15 degrees +- 0.12 degrees on AWD cars). If the computer shows that this spec is out of range, you must adjust a nut that is located on the end of the tie rod (B):



Before you adjust the nut, be sure to loosen the tie rod end from the wheel bearing housing via the horizontal nut (A). Once you have adjusted the nut, tighten (A) back to 45NM and then you can tighten (B) down to 7NM (62 In/Lbs). Then you must re-check the toe difference between unladen and raised to see whether you adjustment helped.

For the rear of the car, you have two adjustment points, toe and camber. There is a larger cam bolt/nut setup on the hinge point of the lower control arm and the wheel bearing housing. The bolt/nut has a travel that moves 180 degrees (rotates 90 degrees to the left or the right) this will adjust the rear camber. I had trouble with this because my car is lowered (H&R sport/Bilsteins). I ended up with -1.24 degrees of camber (tops of tires slightly tilted towards inside of wheel well). I'm guessing the lowered suspension caused this.

The rear toe is adjusted via the rear track link that goes from the rear of the wheel bearing housing to the subframe. Once again you have the cam bolt/nut combo. Even if the car is lowered you should still be able to get in spec on this one.

The last item to mention here is the order for adjusting each of these items. You should move in this order:

1. front camber
2. front toe
3. rear camber
4. rear toe

Always change camber before toe. camber will have a slight effect of the pull against the tie rods/track links.

Hope this helps some of you.

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