Kabouter Posted November 26, 2009 Report Share Posted November 26, 2009 Hi again, it has been a while. I have bought a 2001 330d BMW touring a few months ago. Replaced front control arms, so have new ball joints and replaced to old bushings with polyurethane bushes as I have noticed the rubber bushes can cause the front wheels to move forward and backwards quite a lot under a bit of strain like braking and uneven road surfaces. When driving at lower speeds the steering is nice and solid but quite heavy, faster speeds there is a slight nock on the steering wheel.( not wheel balancing,more like a slight play) The car tramlines quite a bit and is a bit unstable to drive at higher speeds. Before replacing the cheap wanli tyres for T1R proxes and the bushes the drive was a bit more stable except for under braking, where it sort of chose by itself which way it wanted to swerve.(not good) I have an Vauxhall astra with a fully polyurethaned suspension, fully adjustable coilovers and Toyos that has been set up by Tony that is an absolute pleasure to drive. Stable at any speed turns on a penny at any speed and the feedback from the suspension is progressive, ie. do not just break away, it let you know what it is about to do. The BMW has a M-tech II suspension and I feel that it could be much better than it is at present. Even my wife prefers the astra as she says the BMW is a scary drive. I know I have to take it to Tony for a good seeing to before jumping to any conclusions but some feed back and experience would help in getting this setup just right. I am also using the standard tyre pressures as printed in the manual, 2.9 bar on the rear and 2.4bar on the fronts. Are those pressure for RFT? I assume that it might have to be different because of different stiffness in the sidewalls? Sorry for the longwinded post but i suppose the more info, the more accurate the replies will be. Quote Link to comment Share on other sites More sharing options...
Tony Posted November 26, 2009 Report Share Posted November 26, 2009 The new control arms and bushings should reduce the "fore/aft" movement?..... Can you actually move the wheel? Quote Link to comment Share on other sites More sharing options...
Kabouter Posted November 27, 2009 Author Report Share Posted November 27, 2009 No I can not move it by hand. It could move it with the rubber bushings previously. I forgot to mention that I also replaced the ARB rubbers with polyurethane. I still need to do the complete back end of the car. I do not think my problem could be too serious as the MOT was only done a month ago, after I have done the front end work. Quote Link to comment Share on other sites More sharing options...
Tony Posted November 27, 2009 Report Share Posted November 27, 2009 I wouldn't be to concerned, the bushings are designed to allow some movement so providing the car doesn't tramline i would be happy with this. Quote Link to comment Share on other sites More sharing options...
Kabouter Posted November 27, 2009 Author Report Share Posted November 27, 2009 The tramlining is a problem atm, not too bad but it is there. The bigger problem is the twitchiness at highway speeds. To the extend where tramlining and a bit of a cross wind can make the car hard to keep in a straight line, looking a bit like a drunk driver. It is a completely different driving experience to the astra but needs way too much input on the steering wheel to my likingand making it unsafe for a slightly less experienced driver(wife). What do you recon on the tyre pressures Tony? Taking into account that the tyre widths on the astra is only 10 mm less? Quote Link to comment Share on other sites More sharing options...
Tony Posted November 28, 2009 Report Share Posted November 28, 2009 We have been here before...... many times with this "floating feel" at speed and i'm horrified to say it's a design "fail" with a combination of factors from the tyres up. The issue is in the "sprung" area or let's say everything that's resting on the suspension, there's nothing i could change in the unsprung department that would correct the problem. Quote Link to comment Share on other sites More sharing options...
CIH Posted November 28, 2009 Report Share Posted November 28, 2009 wasn't this an issue with staggered tyres too ? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.