14 replies to this topic

[majorj0nny]

so after my mini ?(from purchase) drove like a bag of spanners with it feeling like the entire car was exploding when I went over a slight bump in the road - Ive finally fitted new suspension front and back.

new standard cone springs to replace all 4 totally squished and rusty old ones, 4 new knuckle joints and caps, 4 new lowered dampers (spax adjustable), and Hilo's front and back.

now going off the back - the difference was amazing first time I took her out afte fitting them - actually felt like suspension, and managed to lower the back a bit. as before there was a massive gap?

anyway - first thing, is it normal for the car to sit quite high after you jack it up ? ive noticed this effect after jacking, and putting it back down - the arch gap is massive, even bouncing the car dont seem to have much of an effect till I drive it again, then check and its back down. I was wondering if my hilos or springs were coming out of alignment and resulting in this - but no.

anyway - the back - I set both hilos to roughly the same thread length, but the driver side was finger tight on the arch/tire gap while the passenger side was a good few inches - obviously the driver side was occasionally rubbing the arch when I cornered like this, so I adjusted the hilos back up to try and maintain an equal gap. .... its difficult to do. will parking on an uneven surface give inaccurate impressions of arch/tire gaps ??

the front concerns me more, Ive just noticed the top arms are sitting on the big top bump stops ... now far off these should the tops arms be ? and how can they be on the bump stops when the wheel still have a good few 3? inches between the arch and the wheel ? surely if I raise the hilos up more to stop the bump stop touching the top arm - I'll end up with a massive arch gap ?

I got 12" wheels

[Cooperman]

The back sounds fine and maybe just needs a bit of final adjustment. On an uneven surface it will not have an even gap. When you jack the car up and let it down it will sit high until you drive it a little way. Just get it onto a level surface and set the rear ride height the same both sides using the Hi-Lo's.
The front is another matter. The suspension MUST NOT be on the bump stops as this will prevent the suspension from working properly and will really upset the steering in bumpy corners. Do you have the correct bump stops? The bottom of the wheel arch should be about 21.5" from ground level as a guide, so measure yours and see what you actually have. If you have that and the suspension is correctly assembled, you might have to cut the bump stops down a bit as it sounds like they are incorrect for your car. Alternatively get the correct bump stops. There should be quite a bit of clearance between top arm and bump stop at normal ride height, around 3/8" to 1/2" from memory.

[Jordie]

new cones take a while to settle in and can only be done so by driving the car regularly.

Id raise the front otherwise you may do damage as your cones settle.

Once the cones settle, you should have room for adjustment without hitting the bumpstop.

[Chance]

My front eidw height on the drivers side changes as and when it feels like it

I too fitted all new cones, new knuckles and hilos
Took me a lot of adjusting and driving and adjusting to get it so I was happy
And then of course when the cones start to settle you got to do it again :)

[maccers]

Would there be any or as much settling needed with metal coil springs, ie mini tastic ones?

[Cooperman]

Would there be any or as much settling needed with metal coil springs, ie mini tastic ones?

No, but coil springs are really for track use and there are no springs as good for road use as the real 'rising rate' provided by the rubber cone springs - they were/are a masterpiece of design really and one of the reasons the Mini suspension is so fantastic.

[tiger99]

As Cooperman says, coils are unsuitable for road use. Because even a progressive rate coil can't come near to the rapidly rising rate of the rubber cone, they can't cope with big changes of load in the car. If you fit a set of coils suitable for driver only, it will be hard on the bump stops with four people on board, which is downright dangerous. A set of coils designed to cope with a full load will have it on the droop stops with driver only on board, and not only will it be riding high, but it will be horribly hard, and again the handling will be seriously impaired.

You can't correct the spring rate by adjusting the hilos, they do two very different things.

The Mini suspension, due to the dimensions of the car, has very short wishbones at the front, so the travel must be limited to keep the geometry correct over a range of loads, and there are only two workable ways of doing it, the simple way using non-linear rubber cones, and the complex way using a hydropneumatic sel-levelling system like some Citroens.

[maccers]

Cheers for the replies. I am just completing my build and about to get the suspension set up correctly, but have used the mini tastic metal coil springs. Hmm, might put back the rubber ones then before any final setup is done.

[majorj0nny]

So regarding hilos, what's the best initial setup in terms of trumpet lengths? Or more suitably... How much shall I raise the hilos while the springs are selling in ? I'm guessing I should ignore trying to get the car to sit low at this point ?

[Skortchio]

I fitted Minitastic springs a few months back, they're progressive but not to same level of performance as rubber.
Which is fine because I won't have to change them every 2k miles to retain optimum rubbery goodness.

As Cooperman and Tiger have said, they're not the optimum for performance but are massively more comfortable forgiving (very important for me) and if you don't take varying loads (ie. more than 1 passenger) can make a good option.

They do settle in, like any part.
The backs always look massively high if you've taken the weight off the spings but drop down to the right level as soon as you drive (once broken in).

For the hi-lo setting, measure your sill height front and back at the last 'flat' bit. Aim for the front at about 9.5" and the rear about 11" that's close to standard. Adjust the hi-lo to give this, 1:5 on the back, 1:3 on the front.

Something definitely sounds up with your front end though, my car is a little lower than standard and I still have about 1" between top arm and bump stop.
I can't visualise how you can be on the bump stop with jacked up ride height. But I am tired

Edited by Skortchio, 13 October 2012 - 08:13 PM.

[majorj0nny]

No thinking bout it I think I've set the front hilos too low on the front, the front is only gonna go as low as the bumps allow I'm guessing... So at the moment my front suspension IS my bump stops and as a result my cones ain't getting much weight. Think I need to raise the front hilos till the cones are taking the weight instead of the bumps.

[maccers]

It is mostly just me driving, I may take my younger sons, one or both on the odd trip but usually its just me with little or no luggage. Not a daily driver, spends most time in garage.

[tiger99]

Don't run it on the bump stops, ever. It overstresses the subframe, suspension and shell, and when the bumpstops fail, as they will, ball joint fracture is next, and that can kill.

[majorj0nny]

yeah I raised the suspension yesterday and its much nicer ride actually using the cone springs instead of the bumps.. (obviously).

think Im gonna raise it a bit more, what type of gap should there be (typically) between the top arm and the big bumpstop ?

what type of degree of deflection can I expect ?

my new shocks are adjustable - they are all set to the softest setting at the moment - how best to adjust these ? just trial and error ? a couple of clicks at a time on all 4 shocks then drive and see..?

[Skortchio]

I'm not sure the recommended gap, but I have about 1" betweentop arm and bump stop.

What shocks do you have now? I have Gaz 40 point adjustables and run them at 12 front / 16rear. Usually you would have the rear softer than the front but I find with the springs this makes the back end wallow more than I like.