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2025 c3 ('74-'82) of the Year Finalist - Unmodified
2024 C3 of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
Basic Rear Toe-in Question
A rather basic question, but one I couldn't find an answer to in previous threads....
What difference the does addition of trailing arm shims make at the wheel. where I'm looking to get about 1/16" or 1.5mm toe- in at each.The shim sets come with three size shims, basically, thick, medium and thin! What change would a thin shim make, in mm (or fractions of an inch), does anyone know, please?
A "starting point" would be handy!
Thanks!
Last edited by Stephen Irons; Feb 12, 2021 at 12:03 PM.
For me
A 1/32" shim moved from one side of one arm to the other changes my readings at the front spindle by about .335 difference from one side to the other or about .167" from the centerline at the front spindle of the car
M
I'm not saying that this is the best video, but I worked at a race shop and I had to do C3 vette rear alignments more often than I wanted to. We actually had the laser optical read out with bolt on attachments. As to you question I never found a direct relationship from shim width to toe being a one to one because of the distance. Then you are changing things slightly when pull out one from one side to insert it to the other. It was always a trial and error. I never took the time to figure out exactly how much each shim actually moved the toe. Maybe someone on here does this for a living. I might have done only a few a year and it was always in a hurry.
Use stainless steel shims only!
Many years ago I came across adjustable rear toe setup and I told the boss about them. They could only be installed if you had the body up or off enough. So it was more a racing vette idea. But once installed they were great. In cold weather we could easily add more rear toe in to keep heat in the rear tires down long straights.
A rather basic question, but one I couldn't find an answer to in previous threads....
What difference the does addition of trailing arm shims make at the wheel. where I'm looking to get about 1/16" or 1.5mm toe- in at each.The shim sets come with three size shims, basically, thick, medium and thin! What change would a thin shim make, in mm (or fractions of an inch), does anyone know, please?
A "starting point" would be handy!
Thanks!
Here is my complete DIY alignment method.
First step for changing your rear shims is to get the rear thrust angles correct then adjust for total toe.
I'm not saying that this is the best video, but I worked at a race shop and I had to do C3 vette rear alignments more often than I wanted to. We actually had the laser optical read out with bolt on attachments. As to you question I never found a direct relationship from shim width to toe being a one to one because of the distance. Then you are changing things slightly when pull out one from one side to insert it to the other. It was always a trial and error. I never took the time to figure out exactly how much each shim actually moved the toe. Maybe someone on here does this for a living. I might have done only a few a year and it was always in a hurry.
Use stainless steel shims only!
Many years ago I came across adjustable rear toe setup and I told the boss about them. They could only be installed if you had the body up or off enough. So it was more a racing vette idea. But once installed they were great. In cold weather we could easily add more rear toe in to keep heat in the rear tires down long straights.