Camber/toe change when lowering front?
- Thread starter mwood
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So, I'm guessing no one knows the numbers, maybe?
I'm going to need to pull my springs to get my ride height correct next weekend and will measure as much as I can while I have the springs/dampers out and can move the suspension through its travel. I was just hoping someone had already done so...because it is kind of a PIA!
I'm going to need to pull my springs to get my ride height correct next weekend and will measure as much as I can while I have the springs/dampers out and can move the suspension through its travel. I was just hoping someone had already done so...because it is kind of a PIA!
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Mike,
IIRC Buck may have written something about this in CAT mag in regards to work on the SCF racer. Not sure how that would relate to a stock car.. given ride height, maybe drop spindles and other racing mods... etc... but he might be able to chime in with some info??
IIRC Buck may have written something about this in CAT mag in regards to work on the SCF racer. Not sure how that would relate to a stock car.. given ride height, maybe drop spindles and other racing mods... etc... but he might be able to chime in with some info??
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- 906
Years ago, and several blown up hard drives ago, we did a lot of measurements including camber and bump curves. Off the top of my head, both bump and camber were pretty bad. There was way too much bump and way too little camber gain.
However this was done while experimenting with a non-stock upper ball joint. So it's not apples to apples to a pure stock suspension. (We spent over 40 hours on the task, even designing a new steering arm to correct bump. I eventually decided not to use the design. (I was scared of the flexing we saw from the stock spindle.))
Coincidentally, I've just started gathering my tools to measure this stuff all over again and was planning to do so this coming week. To do it right you have to remove the coil on the side you are measuring while keeping the rest of the car at ride height.
My bottom line for those lowering their cars is to do it in a way that does not make it easier for the suspension to go into coil bind or easier for the suspension to hit the bump stops: I'd never cut the coils! I'd consider the effects of using stiffer springs, or thinner coil spring isolators, or perhaps using the slightly dropped spindles off of those Hillman's originally equipped with bigger diameter wheels. I really hate limiting travel on a suspension that doesn't have a lot to begin with.
Anytime you mess with the suspension, you need to check that anything you've done does not approach the limits of articulation of the various parts like the ball on the rack, the actual ball joints or tie rod ends.
bt
at the beach
However this was done while experimenting with a non-stock upper ball joint. So it's not apples to apples to a pure stock suspension. (We spent over 40 hours on the task, even designing a new steering arm to correct bump. I eventually decided not to use the design. (I was scared of the flexing we saw from the stock spindle.))
Coincidentally, I've just started gathering my tools to measure this stuff all over again and was planning to do so this coming week. To do it right you have to remove the coil on the side you are measuring while keeping the rest of the car at ride height.
My bottom line for those lowering their cars is to do it in a way that does not make it easier for the suspension to go into coil bind or easier for the suspension to hit the bump stops: I'd never cut the coils! I'd consider the effects of using stiffer springs, or thinner coil spring isolators, or perhaps using the slightly dropped spindles off of those Hillman's originally equipped with bigger diameter wheels. I really hate limiting travel on a suspension that doesn't have a lot to begin with.
Anytime you mess with the suspension, you need to check that anything you've done does not approach the limits of articulation of the various parts like the ball on the rack, the actual ball joints or tie rod ends.
bt
at the beach
Buck, that's good info and I agree with your point about ensuring the suspension can maintain travel.
Part of the answer, I'd also agree, is to get rid of the spring insulators and, perhaps, shorten the bump stops to retain travel. The other is to up spring rate significantly to keep the wheel out of the camber curve. So, lots of negative static camber to maximize contact patch in roll and big wheel rate...which can get old on a street car. So, it ends up all being compromises. I'm happy with my current alignment (-1.5 camber, zero toe and about 5 degrees caster), as it is still drivable and the toe setting will allow normal tire wear with the increased camber (yes, some toe out would really help with turn in, for sure).
I was just hoping I could ballpark where my current alignment settings go when I lower the car. I know I pick up negative camber and toe out, just not sure how much for a given measurement of shortening the dimension between upper and lower a-arm.
Part of the answer, I'd also agree, is to get rid of the spring insulators and, perhaps, shorten the bump stops to retain travel. The other is to up spring rate significantly to keep the wheel out of the camber curve. So, lots of negative static camber to maximize contact patch in roll and big wheel rate...which can get old on a street car. So, it ends up all being compromises. I'm happy with my current alignment (-1.5 camber, zero toe and about 5 degrees caster), as it is still drivable and the toe setting will allow normal tire wear with the increased camber (yes, some toe out would really help with turn in, for sure).
I was just hoping I could ballpark where my current alignment settings go when I lower the car. I know I pick up negative camber and toe out, just not sure how much for a given measurement of shortening the dimension between upper and lower a-arm.
Last edited:
66TigerMK1A
Gold forum user
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I've done a lot of mods to my suspension/steering over the years... last project was to move my rotor/caliper/steering arms outboard another 1/4" ( 1/2" total gain with MGB arms )for better geometry ( I scrapped my version of the Lou Anderson accurate ackerman angle setup which worked really well but wore out $300 worth of heim joints way too quickly) . I've also done a few things to lower the car including adjustable Mustang II coil overs, half height insulators, Minx spindles, bump steer studs, etc. etc. ...
I have no 'scientific' numbers though...
If you go to my 'albums' ( have to be logged in ) there is a copy of an old tech tip about relocating the upper 'a' arm for camber gain...
http://catmbr.org/VB_forum/album.php?u=68
Click on " 1976 TechTip Suspension tuning" . You might find it interesting. My car already had this mod when I bought it.
I will probably get busy and remove the springs this winter to 'play' with the bump steer some more as it definitely is an issue
- Buck.. strangely enough, the Minxes that have the relocated axles only have 13" wheels... just acquired a complete car a couple week ago...
Jim
B382000446
) . I've also done a few things to lower the car including adjustable Mustang II coil overs, half height insulators, Minx spindles, bump steer studs, etc. etc. ...I have no 'scientific' numbers though...
If you go to my 'albums' ( have to be logged in ) there is a copy of an old tech tip about relocating the upper 'a' arm for camber gain...
http://catmbr.org/VB_forum/album.php?u=68
Click on " 1976 TechTip Suspension tuning" . You might find it interesting. My car already had this mod when I bought it.
I will probably get busy and remove the springs this winter to 'play' with the bump steer some more as it definitely is an issue
- Buck.. strangely enough, the Minxes that have the relocated axles only have 13" wheels... just acquired a complete car a couple week ago...
Jim
B382000446