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panzershreck
06-11-2004, 11:30 AM
thinking about upgrading the suspension as the first real upgrade to my car, starting with new sway bars... read bmwe34.net, what exactly is the advantage of fully-soft in the front and hard in the rear? and how does it differ from stock in road handling and feel?

Martin in Bellevue
06-11-2004, 11:38 AM
It is an effort to reduce understeer.

I've got the racing dynamics anti sway bars. They are pretty stiff. One bushing in back was shipped the wrong size; they weren't interested in getting me the correct bushing.

Maybe I'd go for just the big latter m5 rear bar, if the opportunity came up.

Robin-535im
06-11-2004, 03:40 PM
thinking about upgrading the suspension as the first real upgrade to my car, starting with new sway bars... read bmwe34.net, what exactly is the advantage of fully-soft in the front and hard in the rear? and how does it differ from stock in road handling and feel?

My understanding is that the RD sways, when set front and back at the same notch, will make the front end much tighter than the rear, resulting of course in understeer.

Setting the front sways to the softest setting (still firmer than stock, but the least-firm setting on the bars) and the rears to the firmest setting is the most neutral balance for an E34.

Difference from stock handling... Much flatter in turns, probably not noticeable otherwise. The road feel of a brand-new E34 with stock sways vs. a brand new E34 with bigger sways might be different. Once you start putting larger tires and stiffer shocks on, I don't see any downside at all to larger sways since you're far enough from the stock ride as it is.

HTH

mholbrook
06-11-2004, 05:40 PM
Probably the least expensive alternative is the M5 bars which are available from BMA and drop shipped to you from Germany. I have the M5 (25mm) bar in front and the M5 Touring Nurburgring (20mm) bar in the rear. The standard M5 bar in the rear is 18mm the Touring is 19mm. I have staggered tires on my car and the 25/20 setup is pretty neutral. I had a 530 with the 25/18 and it was nice but still had understeer. I can rotate the car on the autocross pretty much at will with the throttle on my 535im.

Call Patrick or Yves at BMA (www.bmaparts.com)

Jeff N.
06-11-2004, 06:39 PM
It is possible in the 540, particularily the 540/6 or M5.

However, with the stiff rear bar setting, you can very much get trailing throttle oversteer. Not a happy thing if you don't know what it is and are not ready for it. Can put you in the ditch in a very big hurry in the wet. In particular, it can be *very* dangerous if you have others (wives, girlfriends, etc) that might drive the car.

I would be very careful about cranking down the rear bar and leaving the front bar loose without a good plan as to why you are doing this.

Jeff