How much will worn bushings change camber?

[hoveringuy]

I've gone through and replaced almost my entire suspension wear items except for my trailing arm bushings. I have a little bit of excessive camber in the rear, just shy of 2 degrees and am wondering how much changing the bushings to fresh rubber would restore the camber. How 'bout toe?

Anybody have some before and after data from changing them?

Hoveringuy

[e30_325es]

If you are just shy of 2 degrees (I assume you mean -2 degrees), then you are still in spec. Max specs are -2.3.

How many miles do you have on the bushings? Is your car lowered? I'd imagine it wouldn't change more than 0.1 degrees.

[hoveringuy]

I have 177,000 miles on those bushings. Lowered with H&R.

I'm basing the camber on measurements using a carpenter's square and some trig. The camber is 3/8 measured on the top and bottom of the rim over a span of 15". The math works out to 1.43 degrees but from the rear it looks a lot more /\ and the inside tire wear is annoying. My first step will be to add 10mm lower spring pads and then I will evaluate either new stock rubber or eccentric rubber.

I don't know how much the old bushings flex??

Hoveringuy

[jlevie]

At 177k it would be pretty safe to assume that the RTAB's and subframe bushings are probably pretty far gone. Bad RTABS will affect both rear toe and camber. How much of an affect would depend on how bad the bushings are and you won't know that until you chnage them.

[Maluco]

At 177k it would be pretty safe to assume that the RTAB's and subframe bushings are probably pretty far gone. Bad RTABS will affect both rear toe and camber. How much of an affect would depend on how bad the bushings are and you won't know that until you chnage them.

then what did you mean by "you don't normally have toe and camber adjustments in rear"?

EDIT: Ok, just read this paying attention and I guess you meant you can affect rear toe and camber but don't normally have "adjustments" for them?

[jlevie]

The trailing arm suspension on an E30 has no provisions for adjustment as it came from the factory. There are aftermarket eccentric bushings and adjusters that can be fitted to the trailing arms. So normally there's no adjustment, but it is possible to set the car up so that adjustment is possible.

[Maluco]

The trailing arm suspension on an E30 has no provisions for adjustment as it came from the factory. There are aftermarket eccentric bushings and adjusters that can be fitted to the trailing arms. So normally there's no adjustment, but it is possible to set the car up so that adjustment is possible.

got it, so if you lower the car is stock ok, if you don't really want to adjust it via the aftermarket stuff or should one incorporate aftermarket components if lowering?

[joshh]

Bushings can really be a tire killer. In and of themselves. I would suggest you replace them asap. Static camber is one thing...who knows what those bushings are doing with suspension movement and weight transfer.

[hoveringuy]

I am planning on replacing them.

One other thing to note:

The handling on dry pavement is amazing. It's everything I want.

The handling on wet pavement has become treacherous. I don't know if DC uses special "slippery" asphalt but I never had a problem in the wet before I lowered the car, when I lived in Seattle. I have a hard time accelerating from a signal without spinning the wheels and I need to stay off the gas around most corners.

My working theory is that the camber decreased my contact patch by a few inches and I'm not getting enough weight transfer in the wet to plant the whole tire. It's no fun!

Hoveringuy

[StereoInstaller1]

I am planning on replacing them.

One other thing to note:

The handling on dry pavement is amazing. It's everything I want.

The handling on wet pavement has become treacherous. I don't know if DC uses special "slippery" asphalt but I never had a problem in the wet before I lowered the car, when I lived in Seattle. I have a hard time accelerating from a signal without spinning the wheels and I need to stay off the gas around most corners.

My working theory is that the camber decreased my contact patch by a few inches and I'm not getting enough weight transfer in the wet to plant the whole tire. It's no fun!

Hoveringuy

Sounds like my car when it was on ES100's!

Luke

[jlevie]

The tires and what pressures you run have a big affect on performance in wet conditions. Some tires just don't work well in the wet. And if the pressure is wrong the contact patch won't be right. Too high a pressure and more negative camber will reduce contact patch and if the tires don't work well in the wet (though they may be great in the dry), things get squirrelly.

[hoveringuy]

Yeah, the first thing I did was drop the pressure from 35 to 32 psi. The tires are the same Fuldas that I used to love in the rain. I'm telling you, the slight increase in camber by lowering the car 1 1/2 inches has really made it squirrely in the wet. (or DC uses special asphalt...)

Hoveringuy

[jlevie]

How much tread do the tires have left?

[hoveringuy]

I have about 7/32 left on this set. These are nice and evenly worn because the last time I used them was over a year ago.

I put my bottlecaps with the Fuldas back on while I refinish the basketweaves over the winter.

Hoveringuy

[JRKOUPE]

..I run like neg 2.5 in rear on stiff HR race and all new bushes...and even w/ r tires its pretty planted in wet.......check your toe...or maybe your tires are old and dry...