Here is a method I worked out to do the front toe-in and it is accurate...takes about 15 mins if you are just checking and the toe-in is within specs.
If done right...it beats using angles and tape measures...etc...hands down.
Probably as accurate as at an alignment shop.
Wheel alignment 101:
* Before starting: You need to be sure that your wheels do not have side to side runout...or your attempts to set the toe-in will likely be off. You can check this by rotating the front wheels and watching for any side to side movement...or you could use a dial indicator.
* If you have oversized tires...you will need to compensate for this as far as the diameter of the tire vs the OEM size...which are what the specs are for.
* If your toe specs are given in degrees...you will have to translate this into inches at the tread.
What you need:
* a small laser level....around $10-$12.
* a square aluminum or steel tube...must be straight.
* 2 home-made bungee straps...made using innertube rubber & coat hanger wire....the length depending on the style of wheel...you will need to hook the ends in the spokes or holes in the wheel.
* 10' tape measure
* a 6'... 2" X 4"...not warped.
* 2 jack stands or similar STURDY supports
* pencil or pen
How to do it:
* Find a reasonably LEVEL paved area...this can be more difficult than you might think due to the fact that most paved surfaces are sloped for drainage...but perfectly level isn't needed...a decently FLAT surface is.
* Drive your car forward STRAIGHT slowly with the steering wheel held steady and stop it gradually using the hand brake. Shut it off.
* Using vinyl tape, tape the laser tightly (without tripod) centered on the square alum tube. I use a wrap of tape at both ends.
Or use a lightweight steel tube and use the magnets in the base of the level.
> This tube must be very straight and uniform; and has to be cut at the right length to fit on the most reliably accurate surfaces on the face of your wheels....so that it sits parallel to the wheels surface.<
* Using the 2 bungee straps...strap the tube onto the first wheel at AXLE LEVEL using the vent holes in the wheel and in a close to horizontal position with the laser beam pointed to the front. Keep the tube centered vertically and horizontally; and check that is is sitting flat on the wheels surface on both ends.
* Place the 2 jack stands (or whatever?) 2' or so in front of the car at a right angle to the front/back centerline of the car. On these and AT AXLE HEIGHT, place the 2" X 4".
Check to be sure that the distance from the axle centers to the 2" X 4" is the same on both ends. Mark the position of the 2" X 4" from the car on both ends using chalk on the paved surface you are working on.
* Align the laser beam so that it hits the 2" X 4" (it should be reasonably close to level...use the bubble) and use a pen to mark the exact CENTER of the light spot on the wood. I use arrows & numbers (1) and (2) to start.
* Then, without touching or moving the 2" X 4" or the car, move the laser to the opposite wheel, being sure to place it in the same way, and do the SAME thing. You now have 2 marks at opposite ends of the wood.
* Now, measure the tread to tread width or the DIAMETER of the tire and multiply this by 4.
Set the jack stands and 2" X 4" up out this distance from the first position...using the first chalk marks to measure out 4Xs the tire diameter at each end.
* Assuming that you haven't moved the laser or the car, adjust the SECOND arrow and the number (2) so that the laser beam hits EXACTLY on this mark.
* Then, without touching the car or the 2" x 4", move the laser to the original wheel again. Mark the place where the laser hits with an arrow and label it (3).
* Now....using a caliper or tape measure, carefully measure the distance between marks (1) and (3). Then divide this by 4.
This will equal your CURRENT toe setting in inches....(+) or (-).
Adjusting the toe:
* It's best to have hit BOTH tie rod adjusting threads with penetrant BEFORE starting this whole process.
* IF your steering wheel is off to one side when drivng straight down a road, then you would want to try and correct for this when you adjust the toe.
Centering the steering wheel:
The steering wheel needs to be reasonably close to center in order for your turn signals to be able to cancel correctly.