It's not about whether I believed you, it's about how well were all of the conditions that would lead to misleading measurements under control? Obviously, you weren't correcting them for any known alignment-setup issues, they just are what they are.
Flatness and side to side slope of the place you set up on to get those measurements.
Tire inflation pressures (all four).
Tire tread depths being equal, at least side to side.
Hopefully, the magnet didn't pick up any little piece of magnetic grit between measurements. I hope you realize that I'm not picking on you here. But whenever you're making precision measurements you do need to think of all the potential sources of error that could be involved, and then do what it takes to either minimize them or allow you to correct for them.
I could make the difference between those readings look closer to -0.4° (not exactly 0° or -1.00°), which would be what you'd get from cambers that are both about -0.25° and the car on a side to side slope of only about 0.2" over the front track dimension (62" or so, depending on wheel offset). If you haven't specifically checked your setup area for levelness - and avoided setting a wheel on any local high or low spot - it could easily be that much out-of-level.
Tires/suspension need to be as free of sideways preload as possible. You need to gently roll the car in a straight line into position in your setup area and gently brake it to a stop. You know how when you let the car down off the jack that that corner doesn't settle all the way back down until you drive it? That suspension movement situation is what you have to intentionally minimize, because otherwise sideways tire scrub will hold the car up on that corner and that end.
It's at least possible that your car is unsymmetrical with respect to its front control arm pickup points or its fenders, or the fender locations relative to the suspension hard points, which would cause equal cambers to produce unequal amounts of this 'tuck'. At the 1/8" to 3/16" level, maybe all of these cars are?
Norm
Flatness and side to side slope of the place you set up on to get those measurements.
Tire inflation pressures (all four).
Tire tread depths being equal, at least side to side.
Hopefully, the magnet didn't pick up any little piece of magnetic grit between measurements. I hope you realize that I'm not picking on you here. But whenever you're making precision measurements you do need to think of all the potential sources of error that could be involved, and then do what it takes to either minimize them or allow you to correct for them.
I could make the difference between those readings look closer to -0.4° (not exactly 0° or -1.00°), which would be what you'd get from cambers that are both about -0.25° and the car on a side to side slope of only about 0.2" over the front track dimension (62" or so, depending on wheel offset). If you haven't specifically checked your setup area for levelness - and avoided setting a wheel on any local high or low spot - it could easily be that much out-of-level.
Tires/suspension need to be as free of sideways preload as possible. You need to gently roll the car in a straight line into position in your setup area and gently brake it to a stop. You know how when you let the car down off the jack that that corner doesn't settle all the way back down until you drive it? That suspension movement situation is what you have to intentionally minimize, because otherwise sideways tire scrub will hold the car up on that corner and that end.
It's at least possible that your car is unsymmetrical with respect to its front control arm pickup points or its fenders, or the fender locations relative to the suspension hard points, which would cause equal cambers to produce unequal amounts of this 'tuck'. At the 1/8" to 3/16" level, maybe all of these cars are?
Norm
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