Last February, I wrote a piece about do-it-yourself alignment. I talked about a number of methods, including using strings stretched along the sides of the car, and using two tape measures to measure the distance between the fronts and backs of metal plates leaning against both wheels. I extoled the utility of the method I’d settled on—purchasing an inexpensive toe-in gauge that’s a metal bar with a sprung pointer. You hold it against the midpoint of the rear edges of the tires, set it to zero, move it to the midpoint of the front edges, and the reading is the amount of toe-in or toe-out. The advantage over strings or plates and tape measures is that it’s rigid—nothing sags—and you get a quick measurement. I used the toe-in gauge effectively and efficiently to align the front wheels on my BMW 2002tii.
Read the full column on Hagerty.com:
Nice piece! I would hesitate to center the steering wheel by adjusting it at the column spline, as I've seen steering boxes and racks designed to be a little extra tight at the center area. And of course, my BMWs are pre-marked by the factory for the one and only correct spline. Better to adjust the tie rods in equal and opposite directions.
nice article...you have been doing things with 02's almost as long as me Rob...;-)..glad to see your still messing with them ....we always used a tape measure and string to set the race car toe....for camber,we used a very simple in-exspensive guage...that was magnetic and set on the hubs...
What we need is an article covering "what wheel alignment really is for the laymen and car enthusiast". The front (or rear) suspension geometry is already built into the vehicle. Alignment just confirms that and allows fine adjustment for best wear (or following parts replacement). I could find the time write up a short, easy to understand overview of wheel alignment if Hagerty or others are interested. (50 years +/- in the business)
Yeah, pretty easy to do, if tedious. But don't underestimate finding the centerline of the car, even with solid axle vehicles--rear thrust angle is your enemy. Fresh out of college, I went big with a Hunter C111 in 1985 for my first Porsche shop. Worth it for production, but wholly unnecessary to do the (mainly) 911s I've always had. So today it's the typical--Smart Strings, camber gauge, scales (yeah, corner weighting it important) with roll off pads, and hubstands. Oh, and a kinematic toe gauge for the Rube Goldberg device that is the 993 rear suspension......
Interesting piece of kit there. However, pulling the steering wheel off and moving one spline is a lot harder on my cars. Instead, I adjust the tie rod ends. If it is showing left when straight ahead, you move the left side out in small increments, say 1/4 turn, and move the right in 1/4 turn. That way the wheels match the steering wheel.
I've been using two 4-foot levels with notches filed to hook the end of a tape measure into and to pass the tape from one side under the car. I set them 6-8" off the ground where they clear the undercarriage and take readings on both tapes. The difference is rough toe at the wheel. When I bought the tape measures, I made sure they were both the same scale side by side at 6 feet. It isn't exactly the mid point of the tire but it still gets it dialed in after changing any front end parts.
On your rear toe, couldn't you use something like a long straight edge or a laser pointer to see the angle per side that the tires are angled in or out? If it were crabbing, one would point out past the front tire and one inside the front tire, right? Both toed in would hit the front tires and both toed out would clear the front tires.
A local "alinement" (that's how his sign spells it, and he has a page out of a dictionary on the office wall to back him up!) goes one step further: He asks "about how much do you weigh?" and then simulates that weight via gym weights on the driver's footwell and various clean, cloth-covered sandbags on the seat as he performs the procedure. The results are immediately felt when you pick up your car, and needless to say, you have to schedule an appointment to get in his shop because he is that busy.
"Instead, I adjust the tie rod ends. If it is showing left when straight ahead, you move the left side out in small increments, say 1/4 turn, and move the right in 1/4 turn. That way the wheels match the steering wheel."
Of course, which way to turn each tie rod end will depend on whether the tie rod ends/rack/steering box/drag link assembly is in front of the axle or behind it. On '70s Mopar B- and E-bodies and a '92 Acura Vigor we have, it's behind. On 3rd gen Supras, it's in front. Also, many steering wheels have a master spline that only permits the wheel to be mounted at a specific clocking.
My Uncle taught me home alignment when I was in my teens.
One thing I noticed that was not mentioned, or maybe I missed it, was th at you had to jack up the car to spin the tires, to scribe the line......
One thing my Uncle was insistent on was that after you pulled the jacks, you had to roll the car back and forth to let the suspension system settle in. Always made sense to me.
My toe gage contacts the outsides of the outboard rim beads. Slides under the car then tilts up clear of all the body panels. No jacking up the car, no marking the rubber. Brutally simple and has worked beautifully every time.
A slightly different version of the tramell guage was used for many years in body shops to straighten frames. Several of them were hung from the frame by small chains; each had an upright pointer in the center. You stood behind and underneath the car and sighted down the pointers. If one of them was not aligned with the others you knew that's where the problem was, and applied frame straightening to the area. Once cars switched from full frames to the monocoque design where frame straightness is measured in millimeters instead of the old "half an inch is close enough" it was necessary to come up with something a little more scientific.
Love that gauge Rob! Good story. I've never come across a rim specific toe in or toe out specification. Is that a British Sports Car thing? Maybe just a Sports Car thing?
I use a FasTrax Caster/Camber gauge with toe wings to do my alignments. The toe wings are sufficiently low that you can run your tape measure below the low body, but maybe not low enough for your Lotus with the cute little wheels. 🙂 Yes, it was a cheap shot, but I think necessary. 🙂 (A guy needs some entertainment during this Covid Lock Down).
Thinking about Toe In measuring. It would really depend on where you are measuring the toe. If you measure the toe at the bottom of the tire, where it meets the floor, it will be different than if you measure it at the very front of the tire. As I think about the alignment racks I've seen: They check toe with arms that tend to be far larger than the diameter of the tires. I wonder if there is any sort of compensation in their systems for different wheel and tire diameters?
Toe is a pretty forgiving measurement, on most cars, but I can see where, if you went from say a 25 inch diameter tire/wheel to a 31 inch diameter tire/wheel; the toe in would be different (when measured from the same place on the tire), because the surface is farther from the center of the hub.
Hmmm, might have to dig a bit more into where specific manufacturers want the toe measured? Thanks again Rob for making me think more than I need to! 🙂