Competition Alignment Tips

There are so many variables involved it's impossible to provide one good setting for all cars, but I'll try to give you a baseline settings and a few guidelines for how and when to change it.

And before you go making too many changes, read the rule book for the sanctioning body you're competing with to be sure your plans are legal. Many factory parts are not allowed on "stock" classes unless the parts were available on the car at the time the car was assembled at the factory.

Front Camber

One fairly universal rule is to get as much negative camber in front as you can. (Stop at -3.5 degrees if you can get that much.) On an E30 that means using the factory eccentric upper strut mounts or aftermarket camber plates. On an E36 that means using the factory "crash" bolts, swapping strut mounts side-to-side, or aftermarket camber plates. On an E46 that means removing the camber locating pin on the upper strut mount or aftermarket camber plates. On the street you'll typically want no more than -1 to -1.5 degrees for most street use or you're likely to suffer accelerated wear on the inside shoulders of your front tires, especially if your toe setting is anything other than ZERO.

Remember, changes in front camber affect front toe settings, so if you change your front camber you need to remeasure and adjust your toe for best performance and optimal tire wear.

Front Toe

Lots of controversy here so feel free to disagree. I've always run ZERO toe on any BMW I've ever autocrossed or road raced and found it to work best in all circumstances. So there. <g>

Many people believe that a small amount of toe-OUT improves turn-in. I found that true when I was racing FWD cars -- which will toe-in on acceleration and toe-out on braking -- but I've found that RWD BMW's, with their taught steering and suspension components, don't experience much dynamic toe-changes during cornering and an initial setting of zero provides the best combination of handling and tire wear.

Rear Camber

A general rule of thumb for most of my autocross and road race cars has been to keep the rear negative camber about 1 degree less than the front, e.g. -2.5 in front and -1.5 in the rear. On a Stock category car where front camber is extremely tough to come by, I usually try to get as much negative front and rear as possible, which usually exceeds my "1 degree less" rule in the rear. On E30's the rear is not (easily) adjustable, but fortunately on E36's and E46's the rear is quite simple to adjust.

Rear camber provides stability in cornering, but too much can affect acceleration, braking, and can cause rapid wear on the inner shoulder. So pay particular attention to tire temps if you're running more than -2 degrees on most cars.

Rear Toe

Here's another area of controversy. Many people say their BMW's "push like pigs" and want to dial toe-out in the rear to help the car rotate. This is caused by two things: 1) BMW designs their cars to excel at high speed maneuvers at the expense of slow speed sweepers, and 2) most drivers (surely not YOU!) enter corners too quickly causing the front tires to be overloaded at the moment of turn-in, causing a push. Once you isolate the cause of the push, you can begin to fix it.

Few drivers want to hear that their driving style is causing a problem, but this is true in most of the cases I've looked into. I've found that by altering my driving style slightly (slowing down and/or trail braking into a corner) I've been able to get my cars to rotate into and through most corners and without making alignment changes that would take away from my car's real strength -- high speed transitions -- where you'll make up the most time on your competition. Once you begin to add toe-out (or reduce toe-in) in the rear of a BMW you will quickly lose high speed stability and you've just taken away your car's real strength. It may *feel* better in the slow turns, but you'll lose out on the clock.

So here's what I recommend for E36 and E46 cars: 1/4" total toe-IN. On cars with more than 200 rwhp you may want 1/8" -1/4" more, depending on the course. Rear toe-in helps most under acceleration by... the more power you've got or the earlier you want to get on the power, the more toe-in you'll want.

However, more rear toe-in also means the car will rotate less easily under power and will also scrub top speed in the straights.

For us enthusiasts, one of the beautiful aspects of E36/E46 rear suspension design is that by adjusting the camber (which is easy to adjust) also creates slight changes in the static toe setting (which is very difficult to adjust). So by setting the camber and toe to a preset value, it is only necessary to adjust the camber bolts at the track to make significant handling changes.

As I mentioned before, for most Stock category cars set the rear camber at the maximum setting, then adjust the toe to 1/4" toe-IN. This is a good setting on an average high speed Solo II course or day at the track or driving school. If you encounter an extremely tight course or simply want more rotation in corners, you can adjust the camber to about halfway between full neg and full positive and it will do two things: reduce your rear negative camber and toe-in slightly and at the same time -- perfect for tighter courses.

Street Settings and Tire Wear

There is no "perfect" setting that will work equally well on the track and street. For maximum performance you generally want lots of camber and sometimes a lot of toe. For the street you want neither camber nor toe for optimal tire wear.

If you don't want to install adjustable camber plates or constantly adjust your toe settings -- just set it and forget it -- I recommend no more than -1.5 degree camber in front with zero toe and no more than -1 degree camber in the rear with no more than 3/16" rear toe-in... this will provide good performance on and off the track without significantly affecting tire wear.

Good luck, be safe, and have fun!

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