|
In Reply to: Mission Possible: Need suspension upgrade advice.. posted by E34_M30 on June 18, 2000 at 10:45:53:
Some observations:
RD springs are supposed to be closer to Dinan and M5 than H&R Sport or Eibach, the latter being shorter and stiffer. The former drop the car about 1" front, 3/4 " rear, the latter about 1.3" front, 1" rear. New RD springs may have gotten shorter and stiffer, however, as I notice that their sway bars are heavier than they were a couple of years ago. They seem to be competing more directly with Eibach.
If you go to shortened springs (maybe the H&R OE Sport are an exception if they're not much shorter than stock), you should go to Sport shocks to provide the proper travel. There may be others, but I am only familiar with Koni and Bilstein Sport. Koni are more expensive but are externally adjustable. I have seen good reports on this bulletin board. Biltein Sports are great for reducing brake dive and imprve cornering. HOWEVER, on road irregularities (shallow potholes, bumps, etc,) they are much too stiff and jar the front end hard. A 2" deep pothole feels like I've bottomed the suspension.
If you want improved street handling but retain as much of the stock ride quality, then I suggest minimal lowering and new shocks, but ride with someone who has Bilstein HDs before deciding. My understanding is that they have the same valving as the Sport, and so may be equally harsh. If you want to maximize handling performance, then you must compromise on ride quality. Even then, I'd recommend Koni over Bilstein Sport, even at the extra cost.
Heavier sway bars will reduce body roll and increase apparent spring rate a bit. Dinan and M5 bars are heavier than stock, but not as heavy as RD, Eibach, etc. I think Dinan/M5 are 25 mm front, 18mm rear; the others are 27/19. Most, but not all, are adjustable. Start modest in the front and mild in the rear or you may unpleasantly surprise yourself, especially in the wet. I think most shops would recommend springs/shocks first, then sway bars.
The biggest single handling improvement, assuming you replace worn-out shocks, would come from larger wheels and top qality tires. However, that's also the most expensive step and has its own drawbacks. Large tires (235/45x17) can cause tramlining, a tendency for the car to feel like it's following tracks in the road. I'm told that's somewhat a function of the tire brand, but I don't think you'll find any concensus on which tires are the better - it's an individual thing. Large tires are much more expensive. Top quality 225/60x15 are just over $100 each; 235/45x17 run $160+. Finally, low profile tires provide less protection of the wheels from damage due to bad roads. I don't dare go to 17" wheels here in the Northeast, for example.
© 1997 -
2009
Jump Internet Inc. All rights reserved.
