Do any of you do your alignments youselves? Some of the threads give that impression. If this is the case how do you do it without the racks and everything else a shop has? Or do you own a shop....

TIA

 

I don't yet, but I am about to buy a camber guage and toe guage and start doing my own. I've been talking to a friend who owns an alignment shop, and he says you can get pretty accurate even without the floating plates. He recommends rolling the car a little forward and backward after making adjustments to let it settle in just to be sure. I'm going to try this and start experimenting with toe and camber for autocross.

 

camber is easy, toe is a bit harder.

to measure your camber you need a level and flat surface and at the minimum the following tools

• carpenter square
• tape measure

Then checking the camber is a simple trig problem



Measure the diameter of the wheel at the point where your going to make your measurements. (Line A).

Stand the carpenter square up beside the tire. Measure the distance between the square upright and the top of the tire (Line B), and Measure the distance between the square upright and the bottom of the tire (Line C)

Take the difference of B and C, and divide it by A. Now take the inverse sine of that number, and you have your camber angle.

Example:
A = 470mm
B = 74mm
C = 50mm

B-C = 74-50 = 24mm
(B-C) / A = 24/470 = .0510638
Inverse sine of .0510638 = 2.93 degrees camber

Measuring caster is an extension of the camber calculation. Caster is the difference between the wheel turned 20 degrees off center. Turn the wheel to the left 20 degrees and measure camber. Turn the wheel to the right 20 off center, measure camber and take the difference.

Toe is a bit harder becuase you need to keep the centerline of the car in mind when you set your toe. The more accurate you are here, the better your car will handle.


I use the string method to adjust toe. Set up a string line that is perpendicular to the side of the car See example here. It works well, but again, the more accurate you setup your "rack" the better your results will be.

I have been doing my own alignments for a number of years now. On the EVO you need to remember that changing a little bit of camber results in huge changes in toe.

In front, if you add negative camber you will dramatically increase toe in!!

The rear is a PIA to align because of the multilink design. I have done some"professional" alignments thinking I would get a better alignment only to have the technicial give up. After my last fiasco at the alignment shop I spent that afternoon fixing what they screwed up. never again...

The problem is as you change the camber you affect the toe. Change the toe and you affect the camber. It's not quite as dramatic as the front, but it's really hard to get it right the first time. you just need to fiddle with the camber and toe until you get the right settings...

good luck!!

 

I've seen online instructions for making toe guages out of PVC pipe. All you really need to do is measure 2 places and compare the measurements.

edit: I meant toe guage, not camber.

 

well, yeah the PVC pipe would replace the carpenters square. everything else would be the same.

 

Thanks for all the info. Don't think I'll jump in to this just yet, just really cool knowing that it can be done.

Of course the answer should have been obvious: how did the guys in the 'old' days do their alignments when there were no shops to take care of it for you.

 

OOPS! I meant toe guage, not camber guage. You mark measurements along a pipe with adjustable sliders. Now I gotta go edit the other post.

 

you mean something similar to this guage?


I used to do my alignments with something similar. Problem was that it's very easy to correct the toe between the wheels, but even harder to keep thrust angle set correctly.

The string method is better because your setting the toe in relationship to the centerline of the car. Furthermore, with the strings your keeping that alignment off the car's centerline on all 4 wheels.

 

Chrisw. I really like that setup. Looks like I'm on the way to Lowes for yet another car mod.

Anyway how do you reference the centerline of the car? In the pic of the front it looks like you have something hanging down in the center.

 

you can use a plum line to find the center point. The front is easy, I line it up on the logo. Same for the rear (unless you have debadged your car0.

another method is to make sure the strings are the same distance from the car on both sides.

Using 6ft sections of angled aluminum, I set the string so that your at the following

the tip of the front fender: 38mm

B Pillar door seam: ~90mm

that's what I got, just make sure the strings create a square box centered around the car.

Also, very important!!

you need to prevent the steering wheel from moving when adjusting the toe. I wedged a jackstand (with apropriate padding on the seat) to prevent the steering wheel from moving. You will not be able to accurately set the toe otherwise.