M50...Eibach...?

[Bakkrkr]

Was getting ready to order my springs from tirerack and the guy asked me if I had a 24v motor or not. Told him I wasn't sure. I did a vin search and it says I do. It said I have a M50 2.5. Does it really matter....what part number Eibachs should I get

[Dave M]

Yes you have a 24V motor. 6 cylinders, 4 valves per cylinder. I have the eibachs in my M50, no complaints. Don't recall part numbers, but should be easy to find.

Dave

[Bakkrkr]

Is the 24v heavier or something? Eibach says it lowers the front 1.25, I'm hoping for a little more like 1.5. Did yours go the 1.2 or a little more? Regardless I'm ordering tomorrow just seeing what I should expect.

[Tiger]

You can fine tune how high or how low by the spring shims... be sure to replace this at the same time. If you want a bit higher, put a thicker shim... if it exist... I am not sure.

[Dave M]

These were taken right after ~ 10 years ago and they settled a bit shortly after. Yes, I believe I got more than the adverstised drop. I also used the thinnest rubber spring pads available. These are oooold pics.

http://img.photobucket.com/albums/v11/dave_macisaac/Bimmer/5erbriggs2.jpg (http://smg.photobucket.com/user/dave_macisaac/media/Bimmer/5erbriggs2.jpg.html)

http://img.photobucket.com/albums/v11/dave_macisaac/Bimmer/5erbriggs6.jpg (http://smg.photobucket.com/user/dave_macisaac/media/Bimmer/5erbriggs6.jpg.html)

http://img.photobucket.com/albums/v11/dave_macisaac/Bimmer/5erbriggs4.jpg (http://smg.photobucket.com/user/dave_macisaac/media/Bimmer/5erbriggs4.jpg.html)

[Rustam]

Some say adjust the height by the rubber appropriate thickness of the rubber pads. Beware, that if you have Bilstein Sport shock absorbers you may experience bottoming out of the shock absorbers, like many have. I neglected using much rubber padding myself and in my case, the difference of 10-15 millimeters lower had actually made the Bilstein Sport absorbers bottom out, sending a jolt against the mount each time, and making the ride quality horrendous.

[genphreak]

That's a good height for an e34, IMHO it is not really designed to go lower. Doing so brings the tolerances so close you have to perform miracles with the bump stops (M5 ones are a must, though some (Regal) have cut them down (and glue them in the middle) to achieve the same thing not sure how long that lasts.

The 3mm pads (stock is 6mm), are handy to use to fine tune. Low ride height on an e34 has to play second fiddle to correct spring/shock geometry else you will end up with bad results or a costly crack or two.

Best option is Koni Sports, M5 stops, M5/aftermarket sways and decent sport setting springs (Eibach/H&R, etc.) at M5 ride height and adjustment. Anything else is arguably not as good for non-track use.

[Tiger]

My car came with Eibach that is dated back to 1993... it is way lower than your picture... especially the rear end... I think the front has almost zero clearance to see the top of the tire in relation to the wheel well arch.

[632 Regal]

That's a good height for an e34, IMHO it is not really designed to go lower. Doing so brings the tolerances so close you have to perform miracles with the bump stops (M5 ones are a must, though some (Regal) have cut them down (and glue them in the middle) to achieve the same thing not sure how long that lasts.

The 3mm pads (stock is 6mm), are handy to use to fine tune. Low ride height on an e34 has to play second fiddle to correct spring/shock geometry else you will end up with bad results or a costly crack or two.

Best option is Koni Sports, M5 stops, M5/aftermarket sways and decent sport setting springs (Eibach/H&R, etc.) at M5 ride height and adjustment. Anything else is arguably not as good for non-track use.

The cut down method didn't work for long. Ended up cross referencing some from... Can't find it right now, might have been an X5. I am sure I posted it int the archives somewhere The M5 stops are 3 inch and the ones I got are 3.5 inch, the M5 are 4x the price though and it was silly to waste that much on a piece of sponge.

[genphreak]

Yea too right Tiger- it's always a bit freaky looking at ride heights. It's tough figuring, esp. when you first come to the e32/e34 chassis. My 525 bombaround car is slammed too far but its not tearing up tyres on the rear- but it needs a bit of height back there. BUT when I do raise it a bit (I'm going to swap to a plastic fuel tank) the front will no-doubt drop a bit making the front too low... lol!

As perhaps you and many others know, if you look at the parts catalogue they change springs with literally every model- and even then during production- and they cheat with variable thickness spring pads. On e26 nad e28 they had 3 settings on the rear that you could change by adjusting a C-clip once the spring tension is removed.

I think they do all sorts of things right down to putting the pre-production sample on the scales and then re-check their design calcs and revise spring rates.

Weights vary so much dep. on engine, drivetrain and even equipment level. I'm sure the cars that come with metal fuel tanks are spec'ced that way to give them weight in the rear. A lot of them have the battery up-front under the bonnet too, instead of the normal under the back-seat approach that improves battery life and reduces warranty problems.

But the aftermarket people do perhaps three sets per chassis... go figure!

King springs here in Australia can make a set with the rate you need. One day I will take the best set I have for my 540 to them and get a fresh set made the way I want... what a great road trip that'll be...

[Dave M]

My car came with Eibach that is dated back to 1993... it is way lower than your picture... especially the rear end... I think the front has almost zero clearance to see the top of the tire in relation to the wheel well arch.

This is what mine looks like now. You can't jam a straight hand b/w the tire and wheel well. No bottoming out, no wheel rub etc.

[Tiger]

BMW rides is a bit rough with lowering spring because of the strut setup... Ever dropping spring takes away the cushion comfort we crave on really rough roads and lousy road jobs.

When I did the BMW struts to Bilstein Sport... I didn't replace the spring pads... I am not sure why I didn't do it back then... but on the MB's I do, I make sure it got the thickest pads I can get. Since MB is a typical B-Type suspension, the ride is very comfortable even when lowered. It is a bit too soft from factory to begin with.

[632 Regal]

The cut down method didn't work for long. Ended up cross referencing some from... Can't find it right now, might have been an X5. I am sure I posted it int the archives somewhere The M5 stops are 3 inch and the ones I got are 3.5 inch, the M5 are 4x the price though and it was silly to waste that much on a piece of sponge.

^ WRONG! Just found the stop, it's 2 1/8 tall. Part# 31.33.2.225.377 fits E30 E36 and Z3

RealOEM.com * Part Cross-reference (http://www.realoem.com/bmw/partxref.do?part=31332225377)

[Bakkrkr]

I get my Eibachs...should I get some shorter stops just to be sure...don't really want to pull it back apart just to do the stops

[Tiger]

What shock absorber are you using with the Eibach? You cannot use your factory shock absorbers.

If you use Bilstein Sport, you don't need any stops in front. For the back, you cut about 2" off the factory bump stop.

If you get Koni, you cut both front and back bumpstop 2" off.

Any bumpstop... cut off from the flat side... not tapered side. It is a good investment to buy new bumpstops. It is cheap and the original one is so old by now.

[Dave M]

What shock absorber are you using with the Eibach? You cannot use your factory shock absorbers.



FWIW, I'm using Sachs, listed as stock. 10 years since instal, no issues.

Dave