Ride height changed after CMP/Vincebar

[Cubieman]

I finally got my car back on the ground (4 post lift) after installing a VinceBar/CMP Subframe bushings/Turner monoball RTAB's/all new rear OEM bushings.

My issue is the rear ride height looks to be 1" to 1&1/2" higher than before.

I thought I would use the 4 post lift to my advantage when torquing down the bolts for the control arms (to avoid pre-load) but it seems that didn't quite work out.

At first a figured, duh, no differential is installed, no muffler is installed, no rear seat etc., so that must be why the rear end looks jacked up like a muscle car, due to the missing weight of those components.

I installed the muffler and then hung 100lb of weights from the subframe to simulate the diff./brakes with a negligible effect.

All of my bolts (inner/outer - upper/lower control arms) where simply hand tight when I let the vehicle down off the jack stands and onto the 4 post list, so presumably no bushing pre-load was present.

The only bushings that may have preload are the Turner RTABs as you cannot torque them to spec once the toe plates are installed.

Any ideas? My springs seem to be seated properly..

EDIT: Unfortunately I did not take measurements of my fender to wheel relation before taking things apart but I have many photos of the car before disassembly plus I simply remember how it looked.

Is is possible the shocks got stiff after 1+ months on jack stands? I know I am really reaching there.

[Estoril]

Have you driven the car for a while before taking those 'after' measurements?

[SQ13]

Are your RTAB brackets installed correctly? One time I accidentally flipped the left and right side, so the brackets stuck out instead of sitting inside the RTAB pocket on the chassis.

[dl.m3]

You used CMP bushings which changed the position of your subframe relative to the body. The spring determines your ride height as it compresses between the upper control arm and body.

The upper control arm connects to your subframe on one end. And so it resulted in the ride height change.

Completely normal.

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[Cubieman]

Have you driven the car for a while before taking those 'after' measurements?

No I haven't driven the vehicle yet, still have a few things to install, driveshaft etc.


Are your RTAB brackets installed correctly? One time I accidentally flipped the left and right side, so the brackets stuck out instead of sitting inside the RTAB pocket on the chassis.

I assume they are installed correctly as they only look to go in one way?


You used CMP bushings which changed the position of your subframe relative to the body. The spring determines your ride height as it compresses between the upper control arm and body.

The upper control arm connects to your subframe on one end. And so it resulted in the ride height change.

Completely normal.

CMP claims no change in ride height if car is lowered 1/2"+, my vehicle has BC coils which had the car lowered 1"+, the rear sprears are bottomed out as they were before disassembly.

[m3nt0s]

Have you driven the car for a while before taking those 'after' measurements?

Same exact thing I wondered as soon as I saw thread title. Honestly would get the car buttoned up, driven a bit, and report back. Best of luck!

[George Hill]

Are your RTAB brackets installed correctly? One time I accidentally flipped the left and right side, so the brackets stuck out instead of sitting inside the RTAB pocket on the chassis.

I assume they are installed correctly as they only look to go in one way?
[/B]

They do go *only* one way, but people have figured out how to put them in upside down, I don't think this would affect the ride height though.

Have you rolled the car back and forth? The suspension could be bound up causing the ride height to be misleading.

[Cubieman]

They do go *only* one way, but people have figured out how to put them in upside down, I don't think this would affect the ride height though.

Have you rolled the car back and forth? The suspension could be bound up causing the ride height to be misleading.

I have pushed the rear down via the trunk area numerous times to try to "free it up" to no avail, haven't gone back and forth yet.

So odd that the subframe raising bushings would somehow jack up the rear end this significantly, it must be bound up.

[George Hill]

Pushing down won't get it done, you'll need to roll it back and forth at least 6'.

[eacmen]

Parking brake engaged?

[Cubieman]

Parking brake engaged?

No, cables not connected to lever yet.

Diff, battery and muffler all in vehicle and I've got a 1"+ fender gap whereas before the rear wheels tucked up inside w/ my BC's.

Also, I bought new upper control arms and at first had them on the wrong sides, they are quite similar.

I have the one with the little cutout slot for the headlight leveler on the passenger side.
(33326781626)

[DoubleSidedTape]

Have you compared the length of your new upper arms to your old ones? If they were bent it would give you a higher ride height when you swapped in the new ones.

[Cubieman]

Have you compared the length of your new upper arms to your old ones? If they were bent it would give you a higher ride height when you swapped in the new ones.

Good point, I'll have to check that out.

[Sid_E46]

I had the same issue when I used PSM subframe bushings/risers. They bring the control arm with spring perch closer to the body of the car which effectively reduces the height of the area where the spring sits. Using the same height setting as before will result in a higher sitting car.

[Tbonem3]

I agree. Keep in mind, changes in height at the spring will result in about a 150% change at the wheel.