e31 aluminimum lower control arms, are they are direct swap for the e34?

[BigKriss]

I was looking at Bruno's site, in his suspension guide. (http://www.bmwe34.net/E34main/Upgrade/Suspensions.htm) There is new info about the e31 lower control arms. Apparently they have a spherical bearing instead of a rubber bushing. Do these arms fit on an e34? Realoem.com has different part numbers, suggesting they don't. (http://www.realoem.com/bmw/partxref.do?part=31-12-1-138-477&showus=on&showeur=on)

[Anthony (M5 in Calgary)]

I read on an M5 list they are interchangeable. Quite pricy though due to a much smaller market.

[BigKriss]

your a chamption anthony. I was thinking they where interchangable, why else would Bruno have them there? what e34 m5 forums do you visit?

[Shankster]

I was looking at Bruno's site, in his suspension guide. (http://www.bmwe34.net/E34main/Upgrade/Suspensions.htm) There is new info about the e31 lower control arms. Apparently they have a spherical bearing instead of a rubber bushing. Do these arms fit on an e34? Realoem.com has different part numbers, suggesting they don't. (http://www.realoem.com/bmw/partxref.do?part=31-12-1-138-477&showus=on&showeur=on)

Search roadfly's e31 forum. You will find a pic comparing these two. Funny thing is most of the stuff you find on that forum is inquiring about going the other way and using the e34 arm due to the sig lower cost.

Sid

[BigKriss]

Search roadfly's e31 forum. You will find a pic comparing these two. Funny thing is most of the stuff you find on that forum is inquiring about going the other way and using the e34 arm due to the sig lower cost.

Sid

really? thanks for that shankster. would cost matter that much though, as they don't wear much anyway?

[Anthony (M5 in Calgary)]

your a chamption anthony. I was thinking they where interchangable, why else would Bruno have them there? what e34 m5 forums do you visit?


If I told you, I'd have to, well, you know... ;)

I wonder if the folks that did the thrust arm bush could come up with something for you? Fitting a spherical bush in a cast steel arm would be quite economical if you could find one to fit.

Here's a snip from one thread for confirmation of the E31 fitment:

"I would suggest upgrading to the E-31 wishbone.
LEFT ALUMINUM WISHBONE 31121138477
RIGHT ALUMNIUM WISHBONE 31121138478.
The spherical bearing significantly helped the tramlining and
directional stability after I tightened up the steering box and
replaced other front end parts.
If you examine the aluminum/steel wishbone on the E-34 they have a
rubber inner bushing. The aluminum wishbone used on the E-32/E-34
has the same casting part number as the E-31 only the E-31 version
has a spherical (Delron & steel) inner wishbone bearing.
In fact when I ordered the E-31 wishbones I received one E-31 and one
E-32/34 wishbone and it took weeks to finely receive the correct
wishbone because the casting numbers are identical and the only
recognizable difference is the spherical bearing on the E-31 part."

[BigKriss]

thats exactly what I was thinking Anthony. RRT does make lower control arms with spherical bearings, they are us$230 each. I don't think they will just sell the spherical bushing only though. As for e34 m5 forums, I've found m5board.com. (http://www.m5board.com/vbulletin/forumdisplay.php?f=4)

Thanks for your help again!


If I told you, I'd have to, well, you know... ;)

I wonder if the folks that did the thrust arm bush could come up with something for you? Fitting a spherical bush in a cast steel arm would be quite economical if you could find one to fit.

Here's a snip from one thread for confirmation of the E31 fitment:

"I would suggest upgrading to the E-31 wishbone.
LEFT ALUMINUM WISHBONE 31121138477
RIGHT ALUMNIUM WISHBONE 31121138478.
The spherical bearing significantly helped the tramlining and
directional stability after I tightened up the steering box and
replaced other front end parts.
If you examine the aluminum/steel wishbone on the E-34 they have a
rubber inner bushing. The aluminum wishbone used on the E-32/E-34
has the same casting part number as the E-31 only the E-31 version
has a spherical (Delron & steel) inner wishbone bearing.
In fact when I ordered the E-31 wishbones I received one E-31 and one
E-32/34 wishbone and it took weeks to finely receive the correct
wishbone because the casting numbers are identical and the only
recognizable difference is the spherical bearing on the E-31 part."

[Bruno]

I am thinking making a spherical bearing insert for the E34 control arm, but I don't know if there will be any interest, I might make 2 sets.

[BigKriss]

There are over 3600 members Bruno, there should be a few interested parties.

[av8r]

Bruno,
I own a machine shop. Perhaps we can team up on this and lower the cost.
I am gonna replace the front end componenets soon.
Chris
95 530i, 1975 C-172M

[Bruno]

There are over 3600 members Bruno, there should be a few interested parties.

Build it and they will come right ???

[Jon K]

Bruno,
I own a machine shop. Perhaps we can team up on this and lower the cost.
I am gonna replace the front end componenets soon.
Chris
95 530i, 1975 C-172M


Want to cut me a nicer supercharger bracket than what i made myself? Its planar, 2D no contours. Let me know.

[Bruno]

Bruno,
I own a machine shop. Perhaps we can team up on this and lower the cost.
I am gonna replace the front end componenets soon.
Chris
95 530i, 1975 C-172M

Chris, I also have access to a full machine shop, the spherical bearing isn't rocket science, what I like to do once I get a couple of parts is run them on a race car (the turbo 535i track car will do) for awhile so it can see maximum stress.

This isn't going to be a smooth ride though, I expect most poeple won't want such an animal because of the noise that it will generate. But there is a selected few that will be interested in the best handling and turning cars.

I will keep you posted on the results once we make a prototype.

[Bruno]

Want to cut me a nicer supercharger bracket than what i made myself? Its planar, 2D no contours. Let me know.

REdfive is selling his setup if you are interested.

[Jon K]

nah i've got the whole setup lol i just want to recut my bracket in 3/8" aluminum rather than 1/4"

[bfd]

If I told you, I'd have to, well, you know... ;)

I wonder if the folks that did the thrust arm bush could come up with something for you? Fitting a spherical bush in a cast steel arm would be quite economical if you could find one to fit.

Here's a snip from one thread for confirmation of the E31 fitment:

"I would suggest upgrading to the E-31 wishbone.
LEFT ALUMINUM WISHBONE 31121138477
RIGHT ALUMNIUM WISHBONE 31121138478.
The spherical bearing significantly helped the tramlining and
directional stability after I tightened up the steering box and
replaced other front end parts.
If you examine the aluminum/steel wishbone on the E-34 they have a
rubber inner bushing. The aluminum wishbone used on the E-32/E-34
has the same casting part number as the E-31 only the E-31 version
has a spherical (Delron & steel) inner wishbone bearing.
In fact when I ordered the E-31 wishbones I received one E-31 and one
E-32/34 wishbone and it took weeks to finely receive the correct
wishbone because the casting numbers are identical and the only
recognizable difference is the spherical bearing on the E-31 part."

OK, my 535i, 5spd with 104K miles on it, stock everything (except chip). At some point I'll probably need to refresh my front suspension. It appears that the "upgrade" parts would be:

1. lemforder upper control arms with boge 750i (green insert) bushings (or E34 M5 bushings) AND

2. E31 850 lemforder lower control arms with the spherical bushing.

3. Replace the sway bar links (lemforder too?)

4. Do I need to replace the steering linkage - i.e., idler arm, tie rods, pitman arms, etc. I'm not having any problems, yet, but is this something that should be replaced? Thanks!