Any idea how this would differ from say a commercial alignment system? I go to a setup shop and say, lets go 1/16" out, they use a laser alignment rack and get that effective toe. What will it read on a string box? and on toe plates?
Before I started this crazy business I was a front end/suspension tech for 15 years. I have litterally done thousands of allignments on street cars. My knowledge base is 15 years ago, so I have not used the most modern computerized machines. But back in my day (said with a cremudgeon voice), the machines all based toe measurements on a 24 inch diameter tire. Thus toe plates should read the same (assuming a 24" long plate which is normal) as the machine. But strings measured to a wheel will read less by about 60%.
We use a hybrid string system to get thrust/steering wheel square. Then use toe plates for final adjustment. This way an at track adjustment is done the same way the shop adjustment was made.
No matter how you do it, do it the same way everytime.
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