In Reply to: Racing Dynamics Springs for E34 posted by r o b on January 26, 2000 at 19:02:42:
I am surprised by the numbers you quote. Unles they've changed their design, both Racing Dynamics S.A. (now RD Sport) and Racing Dynamics USA (Electrodyne) advertised 1" in front and 3/4" in the rear. I bought a pair used last year and measured before and after and they did indeed change the car 1" in front and 3/4" (+/-1/16) in the rear. The wire diameter was SMALLER than stock springs, so the shortening adds probably 12-15% to the stiffness, which is not a huge change from stock.
I'm not sure that Andy (below) is correct about the reason for the Italy/Electrodyne spit. I heard it was because Electrodyne was selling additional items under the Racing Dynamics name, not that quality was different. For example, Racing Dynamics USA offers sway bars, and used to offer a strut brace; Racing Dynamics S.A. does not.
Rusting can simply be a case of poor quality control by the powder coating subcontractor on a batch, not necessarily the line. I have a trailer hitch that is flaking like mad, but another from the same company that is perfect after many years. The appropriate question is, did they make good on them?
From what I can tell from their web sites and other press, Racing Dynamics S.A. (RD Sport) is mostly what I think of as flash and glitz style stuff and not performance oriented. Wheels, aero body panels, etc. And their prices are definitely for those not operating on a budget. Maybe their Italien shop puts out specialty make-over cars that include performance upgrades, but they don't seem to offer much in parts.
I'm happy with the springs I have, bought a Racing Dynamics strut brace but haven't put it on yet, and expect to add sway bars in the spring.
'90 535i, sharked, RD stage 1, stage 2 soon.