Camber after lowering

[StereoInstaller1]

Right, Ken, statically it is shitty, but made WAY worse under acceleration. Mine were so crappy I would not be suprised if it were 1/2" toe

[KenC]

What's acceleration? ;)

[shiboujin]

I'm planning on lowering my Eta real soon. I'm buying Bavarian Auto Sport springs. Drop is about 1.25 inches. Do I need to worry about toe?

The toe/camber curves are fairly linear. You won't notice HUGE tire wear at just that much of a drop but it will be noticeable if you keep track of your tire wear. For day to day driving, I don't think you'll notice it though.

It's the actual geometry of the trailing arm that causes the rear tires to toe out when lowered. Even with my urethane bushings that don't really flex, I have toe out in the rear. My 14" tires are so cheap that I don't really care.

You mean toe IN.

Toe deflection will lead to toe out under hard acceleration but day to day driving the toe in will kill your tires regardless of how much play is in the bushings.

But if your main concern is tire wear, 1.5" and under for a drop won't change much tire wear. If you care about geometry, you need at least the weld in kit. Shorter subframe bushings should be your first investment.

[KenC]

The geometry of the trailing arms toes the wheels out when you lower it.

[shiboujin]

The geometry of the trailing arms toes the wheels out when you lower it.

http://www.e30m3project.com/e30m3performance/tech_articles/susp-tech/rear_curves/page-2.htm

The basic trend is that the rear suspension gains toe-in as it compresses past the horizontal position of the trailing arms. Neither the camber curves nor the toe curves show what happens as the trailing arms move down from horizontal, but the solutions are symmetric. Thus the rear wheels would also gain toe-in (but lose negative camber) as the trailing arms move downward past their horizontal positions.

compresses == lowering the car in our situation.

[cdsmith_2002]

Great discussion, thanks for all of the input.

Sounds like C/C plates are not an absolute necessity. I'll slap the Eibachs on this weekend and just set the toe with toe plates in the garage.

Haven't researched all the C/C plate options but for $200-$300, that goes a long way in 14" tires assuming I can get at least 30K miles without the plates, from Fuzion HRi's.

[shiboujin]

C/C == camber/caster plates?

If you want to fix tire wear, it's a good idea but not necessary.If you want the ultimate in handling, it's a must.

[george graves]

Right, Ken, statically it is shitty, but made WAY worse under acceleration. Mine were so crappy I would not be suprised if it were 1/2" toe

Luke don't you have an m20? You can't be doing that much accelerating. :)

No but really - maybe it's the 400 lbs of subs and amps in your car? How much weight do you have in the back?

[cdsmith_2002]

C/C == camber/caster plates?

If you want to fix tire wear, it's a good idea but not necessary.If you want the ultimate in handling, it's a must.

Yes, and agreed!

[Lurker27]

Realistically, someone needs to make RCAs for E30s. It would fix all of these problems. The quick answer is to convert to an E30 M3 front and get their adjusters.

Boy that would be nice

[cdsmith_2002]

I've put springs on 6 different cars over the years. I've never been so pleased as with the results on the 325i. The car is amazingly more fun to drive, unlike any other time I've done this!

[CabbE30]

Cut a coil in front or some drop hats.

[shiboujin]

Cut a coil in front or some drop hats.

[cdsmith_2002]

Cut a coil in front or some drop hats.

No way! She is now perfect!