DYI 4 Wheel Alignment Equipment

My home-made Smart Strings. Much cheaper to make (than buy) and also doesn't get knocked out of place if bumped. Rear

http://carpron.com/multisite/v/Upload/PDoane/IMGA0042+2.jpg.html?g2_navId=x5de927b4

The frames were just clamped until I got the ride height set, then drilled and bolted. The slotted bars and wing nuts make it easy to "lock-in" once the two ends are centered on the center of the wheels.

http://carpron.com/multisite/v/Upload/PDoane/IMGA0043+2.jpg.html?g2_navId=x5de927b4

Grooves machined into the bars make sure the front and rear are equal.

http://carpron.com/multisite/v/Upload/PDoane/IMGA0001+15.jpg.html?g2_navId=x5de927b4

Front

http://carpron.com/multisite/v/Upload/PDoane/IMGA0001+16.jpg.html?g2_navId=x5de927b4

fishing reels with very thin monofilament line are used for "strings". A big washer tied to the end of the fishing line gets wrapped around one end. The weight of the reel keeps things taught but allows for "bumping" into the lines.

http://carpron.com/multisite/v/Upload/PDoane/IMGA0002+17.jpg.html?g2_navId=x5de927b4

http://carpron.com/multisite/v/Upload/PDoane/IMGA0003+14.jpg.html?g2_navId=x5de927b4

padding prevents scratching the paint

http://carpron.com/multisite/v/Upload/PDoane/IMGA0004+13.jpg.html?g2_navId=x5de927b4

In reply to PDoane.

Nice set-up! Ditto on the fishing reels. Best to use a fishing line with a bright flourescent color for those of us with older eyes.

For the visual folks:

http://www.youtube.com/watch?v=sZoL1gaWedA

That might help understand what everyone is talking about.

In my shop I have places painted on the floor in which I stack floor tiles. which have been stacked and counted to be perfectly level at each corner of the car.

A bit of grease b/t one layer of the tiles allows the tires to move around and settle easily.

I use two ceramic tiles at each corner.. with Vinyl floor tiles used to shim everything up to level..

A clear tube filled partially with water works great to get everything level.

bravenrace wrote: Maybe when you're running in the snow it doesn't, but on pavement it does require a lot of precision.

Spoken like someone who has never made alignment adjustments at the track between runs. Maybe if I start running on rubber band thin tires instead of 225/50s.

In reply to HStockSolo:

Don't mistake my lack of knowledge about alignment kits as a lack of knowledge or experience in doing alignments. If you don't think precision is necessary in an alignment, well that's up to you. I do.

In reply to bravenrace:

It might be vehicle dependent so YMMV. But I was surprised when I started doing alignments on Subarus that the factory tolerance was +/- 3mm! I checked the alignments of other Subarus (some had just had an alignment done) and the numbers were within spec yet still were crazy mismatched and definitely off from what I would consider acceptable.

I learned that as long as you have a flat floor, jack stands, slip plates, string, basic math, and some form of measurement to sub mm or 1/64 inch then you can do your own alignment that is very accurate. I use a cheap digital level to do camber. You WILL get better results because you care far more about your alignment than any shop will ever care.

The first time it took me hours to figure everything out using the string method. Now it takes me about 30-45 minutes to do the alignment on a Subaru including adjustments if nothing is broken or corroded. I suppose I could be even faster if I used toe plates and lasers but I dont see the need right now since I have not been doing any autocross.

maybe its just my car but i need the precision of an actual alignment rack to be happy. cross caster has to be .38 to .41 to the left other wise she pulls on crowned roads. i am also very particular how i like my alignment i keeps my rears at .15 degress toe in and -2.8 camber. and front at str8t ahead 5.2 and 5.6 caster and negative .7 camber.

In reply to Ojala:

Thanks. Good points. The only thing I would say is that any good alignment tech doesn't go by factory specs, because they are always like what you describe. I used to align cars with the drivers sitting in them, because in many cases it really does make a difference. When you do alignments for a long time, and see customers come back time and time again (back when I did it, cars had full alignment capability and also needed alignments way more often then they do now), you see how they're tires are wearing and what their complaints are and make adjustments to the alignment in accordance with that. How a person drives even effects how the car should be aligned.

I am wondering if some cars are more sensitive to alignment than others. It is entirely possible that Subarus are just less responsive to very precise alignment versus a less precise alignment. That could be a function of the AWD and the sucky strut geometry but I am really not sure.