suspension alignment settings - again

Spriteracer

Member
 West Wales
Hi all,
Sorry this is a bit long. I have a late 2006 E86 sport. (not M). Have now replaced just about all the suspension - springs, dampers, top mounts, wishbones, drop links and all the bushes. Rear anti-roll ( stabiliser) still to do as on back order from Germany and which was very corroded. Drop links and bushes done. all as OEM spec. Painful but necessary.... Also had full 4 wheel alignment done and all readings in the green.

I had hoped this would sort out the tramlining and although it is better it is still not a relaxing drive, especially on a busy dark wet motorway. Much better on smooth open roads, awful on the bumpy back lanes we have in West Wales.

Still to address the tyres (currently half worn Bridgestone RFT) but will have to use new RFTs probably Goodyear or Michelin as I do long journeys with a full boot and therefore nowhere to put the wheel if I have a puncture. Not expecting a huge difference there.

From much reading and my own racing experience with the Sprite, (50's/60's technology, but feels very much like the Z4 although the Sprite is more stable..) an increase in -ve camber and a touch more toe-in seems to be the next step.
Current settings are as follows which seem pretty close to others I've seen, and the car runs dead straight on a smooth flat road.

front
toe - left 0.05 deg. right 0.07 deg. total 0.12 deg
camber left -0.55 deg. right -0.51 deg
rear
toe left 0.13 deg. right 0.10 deg. total 0.23 deg
camber left -1.22 deg. right -1.28 deg

As a comparison the Sprite runs 1/8th inch toe in and -1.5 to -3.0 deg camber depending on tyres at the front, and similar settings to the Z4 at the rear i.e a touch of toe-in and -1.5 deg camber.

As a start I will push the camber to max without pulling pins and add half a turn each side to increase toe-in. So, does anyone know off hand the TPI of the tie-rod / track rod end thread ? I'd like to know so I have an idea how much change I'm putting in without having an alignment check again. I have a basic camber gauge (pendulum) and toe-in gauge (big "C" type) so I can measure in mm, but probably not as accuratly as the Hunter kit does in degrees.

Any other suggestiions gratefully received.

Many thanks.
 
Spriteracer said:
Still to address the tyres (currently half worn Bridgestone RFT) but will have to use new RFTs probably Goodyear or Michelin as I do long journeys with a full boot and therefore nowhere to put the wheel if I have a puncture. Not expecting a huge difference there.

I'm afraid i disagree with you here. This DOES make a huge difference as you will see reading across the website. The tyres are a key element to transforming these cars - for better or worse.

Running max camber on rigid walled tyres doesn't sound like a great plan to resolve handling issues when you think about the dynamics (lack of) of the tyre in question.
 
These are my settings and the car drives perfectly, perhaps slightly twitchy on a straight but that comes with the benefit of very sharp turn in.

I'd also agree with the above, binning the run flats is a huge part of how these cars drive. Get a compressor and a tyre seal kit, along with breakdown cover. That's all I've ever used and I'm taking it on a 2 week trip to Europe this year with the same setup.
 

Attachments

  • IMG_1559-1.JPG
    IMG_1559-1.JPG
    132.1 KB · Views: 394
Thank you both. I wasn't planning on pushing the camber beyond the approved setting, just making sure it was at the most beneficial end of the envelope. I agree with Darkangelv2's comment on that. I have obviously seen an enormous amount of comment over the years on the run flat or not issue, and it may well be that I end up ditching them as well on this car. At the moment I'm loath to as I will be using the car for the next 3-4 months for a long weekly commute - W. Wales to London, and the roads are getting progressively worse.

Just to add though I have had BMWs from E21 through to F21 including E46,61,92 and F21 all on runflats and they were all stable. A bit harsh certainly but they did steer where you pointed them. I find it hard to understand that in the light of all that BMW should release a car so obviously flawed in that respect. I love the car generally, but having had it for a month now am finding it hard not to be a bit disappointed.
 
Also - I see that that the front camber Mjennings23's car is a full half degree greater than on mine. Can I ask is that still standard or have you pushed it beyond the limiting pin ?

Thanks again
 
Back
Top Bottom