Coil over Adjustments

[YaroM3]

lowered my m3 on BC coilovers. while adjusting the rear of the car, measured both sides to same specs, pre load, ride hight etc all measurements are the same. bolt everything back up put the car on the ground take it up and down the street so all settles.
Left side of the car in the rear sitting lower than the right side of the car...... any input on this would be great.
checked everything over multiple times everything seems to be in place and in order alignment was recently done as well, have turner lower control arms as well.
any input would be appreciated.

thanks.

[r4dr]

How much lower is it?

[erickhoyos]

You probably shouldn’t have messed with the preload unless you’re really dedicated to get the best performance. Maybe something isn’t bolted on right or some bushing gave out. I have BCs as well and I just removed the adjustable collars for the spring perch to get the lowest ride height possible in the rear.

[YaroM3]

How much lower is it?

About 1/4 lower.

[YaroM3]

You probably shouldn’t have messed with the preload unless you’re really dedicated to get the best performance. Maybe something isn’t bolted on right or some bushing gave out. I have BCs as well and I just removed the adjustable collars for the spring perch to get the lowest ride height possible in the rear.

I replaced the lower control arm bushings when installed lower control arms. What setting you put your shocks ? I screwed mine until they stopped( basically lowest as they can go) same with the spring perch. Other wise the springs would just move around freely.

[oceansize]

This is something that is common on these cars but I don't know the cause. I have to set my passenger side adjuster about 9 mm higher than the drivers side to achieve a 13.25 inch ride height on both sides. There were quite a few threads on the old m3 forum asking or commenting about this. I'm wrapping up my diff upgrade and Ground control ARCA install so I'm curious to see if the "issue" persists.

Edit: Although on the old forum threads it was always the passenger side, never the drivers (left) side so that is unusual.

[YaroM3]

This is something that is common on these cars but I don't know the cause. I have to set my passenger side adjuster about 9 mm higher than the drivers side to achieve a 13.25 inch ride height on both sides. There were quite a few threads on the old m3 forum asking or commenting about this. I'm wrapping up my diff upgrade and Ground control ARCA install so I'm curious to see if the "issue" persists.

Edit: Although on the old forum threads it was always the passenger side, never the drivers (left) side so that is unusual.

Very odd. First time around I figured my pre load or measurements were off, see it different couple adjustments and always left side came out lower. Just gonna keep looking into it. Other wise will just set the left side a bit higher and call it a day.

Also would ajusting my camber mess with my alignment? Got alignment done and camber on left is more than the right. Left is more tucked in over other side.

[COVID-19]

I would just drive it around and check again.

[erickhoyos]

I replaced the lower control arm bushings when installed lower control arms. What setting you put your shocks ? I screwed mine until they stopped( basically lowest as they can go) same with the spring perch. Other wise the springs would just move around freely.

I never really touched my shocks but it’s basically as it came in the box. The instructions say you’re supposed to adjust preload as you lower/raise the spring perch but I’ve read and seen videos saying you shouldn’t touch the shock unless you choose to. My springs are actually snug tight. I have played with the dampening which is set to something like 16-18 clicks which is the middle setting somewhat. I have seen your comment about your camber being off compared to the right wheel. How much camber does each wheel have? When I did my alignment i had -2.8 degrees to both rear wheels.

[YaroM3]

I never really touched my shocks but it’s basically as it came in the box. The instructions say you’re supposed to adjust preload as you lower/raise the spring perch but I’ve read and seen videos saying you shouldn’t touch the shock unless you choose to. My springs are actually snug tight. I have played with the dampening which is set to something like 16-18 clicks which is the middle setting somewhat. I have seen your comment about your camber being off compared to the right wheel. How much camber does each wheel have? When I did my alignment i had -2.8 degrees to both rear wheels.

I believe my camber is -1.6 right -1.7 left. I'd have to check.
do u compress the shock when u reinstall it ? To get it to the location we're it bolts to the hub. Or twist the bottom untill it reaches it instead of compressing the shock by force.

Usually if you were just adding lowering springs you'd compress shock to get it to the location to bolt up and that's all.

[erickhoyos]

I believe my camber is -1.6 right -1.7 left. I'd have to check.
do u compress the shock when u reinstall it ? To get it to the location we're it bolts to the hub. Or twist the bottom untill it reaches it instead of compressing the shock by force.

Usually if you were just adding lowering springs you'd compress shock to get it to the location to bolt up and that's all.

Yeah I just compressed the shock a little so it can bolt on to the hub. I don’t think your camber should affect the big difference in ride height if it’s so minuscule. Seems to me something is either bent or not bolted on right. Have you messed with the dampening at all?

[YaroM3]

Yeah I just compressed the shock a little so it can bolt on to the hub. I don’t think your camber should affect the big difference in ride height if it’s so minuscule. Seems to me something is either bent or not bolted on right. Have you messed with the dampening at all?

Yes, I had it set at about 20 clicks. Car rode rough really stiff. I set it to 11 clicks and much better.

[Tbonem3]

I've always read the opposite, that the left, driver side sits a bit higher as they tune from factory for a driver's weight in the car.

[YaroM3]

I've always read the opposite, that the left, driver side sits a bit higher as they tune from factory for a driver's weight in the car.

That's what everyone seems to be saying. Going to order and replace all the rubber pads that belong there. And triple check I put everything back as it should be .

[Epsilon]

That's what everyone seems to be saying. Going to order and replace all the rubber pads that belong there. And triple check I put everything back as it should be .

You know your BCs have independent ride height adjustment, right? It means you can adjust your height without affecting preload.