The Definitive Alignment Guide for your E36

You may have all the Go, but its not going to help you without the Stop and Turn functions of your E36. Make sure it grips for dear life when you push it with the stiffest springs and thickest strut braces. Discuss all 1992-1999 BMW 3 series Suspension, Steering, and Braking related issues here.

The Definitive Alignment Guide for your E36

Postby Caligula » Tue May 13, 2008 2:47 am

Our thanks to member "joenationwide" for composing this guide.

With so many posts asking about how to get the car aligned, what shops will align the car, what are the right specs, and why do I have tire wear.....I think we need a definitive alignment guide here.

Part I

Q: What is the Stock E36 Alignment Adjustability?
A: A stock E36 has the following adjustments - front toe, rear toe and rear camber.

Q: Can only certain shops align my E36?
A: There is nothing special about aligning your E36. Now, aligning your E36 per the manual maybe (because of adding weights to car). But the factory specs are shit and you can forget about them.

Q: Can I just take my car into a shop and ask to get it aligned?
A: Only if you dont care about performance and tire wear.

Q: What the hell does that mean?
A: If you bought an E36, you obviously are looking for performance (or if you bought it for image, status, pimping, flossing, hardparking, etc, please GTFO! ). The BMW factory specs care nothing for performance or tire wear, only for safety and a low # of lawsuits. YES I AM SAYING THAT THE BMW FACTORY SPECS WILL NOT ONLY GIVE YOU POOR HANDLING AND PERFORMANCE, IT MAY ALSO WEAR OUT YOUR TIRES PREMATURELY.

Q: Ok, so what is a good performance alignment for the street with good tire wear?
A: Here are the specs:

Front
Camber: -2.5 deg
Toe: 0

Rear
Camber: -1.5 to -2 deg
Toe: 0.20 total toe in (IIRC this is 1/8" total toe in)


Q: Can I get a good Performance Alignment for the Street with stock adjustments?
A: NO! You can not get a good performance alignment for the street with a bone stock E36 M3, or even with a modified suspension, without front camber adjustment . You need some form of front camber adjustment that doesn't come stock.

Q: Why do I need front camber adjustment?
A: Here is the short explanation (long explanation explained later)...your E36 came from the factory with an alignment that gives the rear tires more grip than the front. This means, when you are going around a turn (say an off ramp) and you are at the limits (tires are squealing), your front tires are giving up and the car does not turn. That is much safer than if the rear tires gave up first and you are now spinning around. But when the front tires give up long before the rear tires, you are giving up a lot of cornering ability vs. a car that all 4 tires give up at the same time. And a car that wont turn feels like crap.

Q: How do I get any kind of front camber adjustment, and how much will it cost?
A: Here are the options:

Install shims at lower strut mounts
- ($0.10 to $10)
- easy to install
- gain about -1 deg. camber (about -2 deg total)
- may have tire clearance issues with coilovers

Swapped 96+ M3 upper strut mounts
- (free to $75 used)
- relatively easy to install
- gain about -2 deg. camber (about -3 deg total)

Camber/Caster plates
- relatively easy install
- gain up to -3 deg. camber (range of -1 to -4 deg total on avg)
- lower stack height, allows for safer lowering of car
- 2 way caster adjustability

Q: How much negative camber is safe to run on the street?
A: Up to -3 deg is safe to run on the street. (I run -3.4 deg on the street).

Q: Wont too much negative camber kill my tires?
A: Negative camber does not kill tires. Negative camber plus excessive toe (in or out) causes inner tire wear. Toe (in or out) in effect forces the car to "drag" the tire down the road, where 0 toe lets the tire roll down the road. Make sense? Negative camber will cause the tire to roll on the inside of the tire, but negative camber plus excessive toe will drag the inside of the tire down the road causing bad inner tire wear.

Q: So why are the insides of my rear tires worn after I got a factory alignment?
A: Because factory specs call for lots of negative camber and LOTS of toe in. Very safe but bad for tire life. (Another cause for bad rear tire wear is worn out trailing arm bushings (RTABs) giving you dynamic toe changes.)
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The Definitive Alignment Guide for your E36

Postby Caligula » Tue May 13, 2008 2:49 am

Part II

Q. How does camber affect performance?
A. To maximize cornering force from your tires, the tire must be square on the road during a corner to achieve max grip. If your car had zero camber (all tires square to the road when driving straight), as soon as you turn, the body will roll to the outside, and the outer tires will roll only on the outsides of the tires. Thats why if you ever drove a car with stock alignment hard in turns, you'll see the outsides of the tires worn.

Q. Why does the M3 need more camber in the front?
A. Because of the M3's suspension geometry. Simply put, as the car rolls in a turn, the outside wheels' suspension compresses (makes sense right?). The rear suspension was designed to gain negative camber as it compresses. So as the body rolls, the tire does not roll over as much as the car's body roll, maximizing the tire's contact patch. The front suspension is different, it does not gain negative camber as it compresses (during body roll in a corner), and therefore allows the tire to roll over to the outside edge, minimizing traction. This is why you must give the front end more negative camber to begin with. (Another very popular M3 trick is to run a stiff front sway bar, to limit the front body roll and maximize tire contact).

Q. What is a proper alignment procedure?
A. Before you get your car aligned, you should know what will happen. The shop will put your car on an alignment rack, and put sensors on the 4 wheels. Some racks have a hard time with very low cars, or cars with spoilers (the Beissbarth rack). BMW suggests weighting the car in several areas. This is fine, but not necessary. At least, it would be good to place weights in the driver's seat equal to your weight. But again, not critical.

The tech should start at the rear of the car, where he can adjust toe and camber. Rear Toe is adjusted by loosening the 3 bolts that hold the rear trailing arm to the chassis. If you push the arm inward, you get toe in, outward gets toe out. To adjust camber there is an eccentric bolt where the lower control arm bolts to the spindle (or wheel hub, correct term?). Anyway, once this is loose, it can be turned to adjust camber. It has a cam shaped profile, the base circle of the profile gives the most positive setting, the high end of the "cam" gives the most negative setting. Once the settings are reached, the tech will re-tighten the bolts, (if he's good, he'll do it carefully so as not to affect the positions when tightening, which you'll see when the numbers don't just quite match).

In the front, all that can be "adjusted" is toe. This is just a matter of loosening the tie rod jam nut, and then adjusting the tie rod length, and then tightening down. If the car has camber plates, it can be adjusted at the top of the strut (under the hood) and the tech CAN do this.

Q. What should I do before I get an alignment?
A. Know what you want from the car. Know what settings you want, or the shop will give you factory settings. Do you want the best performance with good tire wear? Then you need to address your front camber issue. Either shims, swap some 96+ strut hats, or camber plates. If the shop can install this for you, fine (it'll cost you), but don't assume they will.

Q. How do I find/install the shims?
A. First you need to find shims. It is basically a washer, with a hole that fits over the lower strut bolt (at least 10mm IIRC). The washer should be about 0.10" thick. This should give about -1 deg more camber. Do not go much bigger, as you will lose thread engagement (the bolt will not go in all the way). A 0.10" is perfectly safe. All you do is jack the front wheel off the ground, remove the wheel, and remove the 2 lower strut bolts. Then insert the shim between the strut and the spindle, and reinstall. (***Note*** This method will pull the tire closer to the strut and spring perch. If you have coilovers, you may need to run a 5mm spacer (or so) if the tire begins to rub the spring perch. Should not affect non/coilover cars.)

Q. How do I find/install the 96+ upper strut mounts?
A. If you have a 95 M3, you can find some used on bf.c. If you have a 96, 97, 98, or 99 M3 you already have these. These upper mounts or "top hats" are a steel plate with 3 studs to bolt to the shock tower, and a ball bearing in the center that holds the top of the strut shaft. You'll have to remove the entire spring/shock assembly on each side, and using a spring compressor to keep tension on the spring. Then you will need an impact tool to remove the top strut nut. Once the nut is off, you simply swap the strut hats from Left to Right, and reinstall. You should have about -2.5 to -3 deg. camber. Don't forget to get an alignment afterwards.

Q. So why bother with camber plates?
A. Camber plates give you the most camber, and it is always adjustable. Some people will max out their camber on track/autox, and then adjust it back to a milder setting for the street. (Personally I just leave it). Also, most camber plates also allow for 2 different caster settings. (I wont go into this discussion, it is generally accepted to get as much caster as possible, but I've heard M3 drivers who prefer less caster, anyway....). Finally, I run Vorshlag camber plates because they have the lowest stack height (and a larger ball bearing center, for more info http://www.vorshlag.com). This means that if you lower your car, it does not compress the strut as much so you have more travel (no bottoming out), and it lets me run my spring perch higher, more adjustment range for coilovers.

Q. How does toe affect performance?
A. Toe behaves similar at either end of the car. Toe in will stabilize the car, making it track straight and not want to change direction. Toe out does the opposite, makes it twitchy, and want to change direction quickly. A car is more responsive with toe out, but less stable.

FRONT Of CAR - Toe-out in the front lets the car turn in nicely, but may "tramline" down the road (finding grooves and irregularities and following them). Toe-in front makes the car hard to turn and want to "push" or understeer (BTW this is what BMW recommends!).

REAR OF CAR - Toe-out in the rear is pretty dangerous for RWD cars, makes the car want to spin, especially under hard braking. Toe-in rear will keep the rear stable, and (here is the key) allow for you to put power down as early and as hard as possible without wheel spin. More is not always better, racers will always adjust these settings till they get it just right. For the street, the suggested settings will let you set-it-and-forget-it.


Q. What is a good track/autox alignment?
A. Most track guys already know what to do here, but for general FYI, a good baseline is:

Front
Camber: -3.5 deg
Toe: 0 (0.10-0.20 total toe out for autox)

Rear
Camber: -2.0 to -2.5 deg
Toe: 0.20 total toe in (IIRC this is 1/8" total toe in)


You'll notice it is just slightly more aggressive than a good street alignment. Any more than -3.0 deg camber and 0.10 toe (in or out) per side can lead to inner tire wear with lots of highway driving.

Some race cars (on race tires) will run even more camber. For race cars, suspension and weight (and usually the track) always plays a role in alignment.

Q. Why believe the author?
A. You don't have to. I'm not part of a professional race team or anything. But I've done a lot of research, a lot of tuning, and a lot of listening to faster racers. I've had my M3 since 2004. Since then I've learned to develop and setup my M3 competitively for autox and track. In 2005 I was mid pack in my autox class. In 2007 I was beating (and getting beat by) national trophy winners. Also in 2007 I started doing time trials with NASA, and held decent times at VIR (which will be improved upon!), and got 3rd place at Redline Time Attack - Summit Point (behind two superb BMW drivers). Also became a certified NASA Instructor earlier this year.

I also drive my car on the street, and can't afford uneven tire wear. I DD, autox, and do track events all on the same tires, so they may not last more than a year, but they are usually worn evenly. I have worn tires unevenly, and it was because I was running the wrong alignment settings (usually too much toe!)
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Re: The Definitive Alignment Guide for your E36

Postby MIKEGTR » Tue May 13, 2008 11:17 am

very informative post... thanks to joenationwide and Caligula for putting this up...

+1 on Toe Out causing ur car to tramline... even on track toe out makes ur car do that when going over rumble strips (even MORE so during braking)...

once u get the feel for it... it becomes really really fun to drive though...

thanks for ur effort guys

Mike
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Re: The Definitive Alignment Guide for your E36

Postby veriest1 » Sun May 18, 2008 10:51 pm

Here's a tip from the autox Miata guys. I'm not sure if it applies to e36's (or that it's even correct since I haven't tried myself) because of the differences in suspension but meh... here it is anyway. Its been a while since I've thought about suspensions so I need a refresher in the finer points. Feel free to correct my info until it's correct.

When getting a performance alignment request as much caster as possible. I believe it's negative caster you're looking for here - anyway, the kind of caster that angles the top of the hub and strut towards the driver and then request as much camber as the factory adjustments can give you after the caster is set.
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Re: The Definitive Alignment Guide for your E36

Postby GotCone? » Thu Oct 09, 2008 7:08 am

It's positive caster, and helps ALL cars.... not a big issue on E36's, but on some cars, too much caster isn't a good thing, depending on what type of racing you do.
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