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Hi there - looking for some advice on coil spring suspension systems - the springs that replace the rubber donuts....

I was sold on the system after taking a trip in a mates van that rode very smoothly - as I was building a cruiser of a car - I though this was a good idea! I have fitted the 'fast road' specification springs to my Cooper and was advised that the Kayaba Gas Upgraded Shock Absorbers sold by Mini Spares were a good shock to use with these springs.

I am running the car with a good 2 + inches of travel between the wheel and the arch - so not low. I have triple checked that I have done everything up on the suspension - but experience a real clatter and banging when going over rutted roads. I am coming to the conclusion that the shocks absorbers are not man enough for this application and can't withstand the shock of hitting the minor potholes that litter our roads......

What to people think? What should I do?

Easy way - change the springs for Mini Spares rubber donuts and leave the shocks...
Hard way - Upgrade the shocks and keep the springs - (need to remove twin tanks to do so) - if so what would you recommend?

Many thanks in advance. Cheers Mark

I ran a set for about five years in my sprint


they wont be going back into it, that's for sure


you have to fit it all with helper springs and anti roll bars to stop it all falling out if you go over a bump and to control the roll (or turn the shockers up rock hard) - the springs are not progressive like the rubber stuff............

sure, on smooth tarmac they are great, but hit a pothole, or a speed hump and BANG they just bottom out.

I was forever refitting arb mount bolts as it used to just snap them off with the shock of the impact


I think that 99& of the people who rave about them have fitted them to a tired old mini with shagged, flat rubber cones, so have no idea how sweet a mini can handle and ride on decent new rubbers


horrid things

Agree with Rich 100%; especially, about why people like them. Don't forget that one should also use the special, big upper arm rebound buffers and the special rear bump stops with the springs. I've installed a lot for people who insist they want them, and they install easily, but you'll never see them on any of my Minis.

Many thanks both for you advice and opinions - I am in total agreement. Rich - I'll give you a call tomorrow and you can sell / send me 4 x rubber donuts

Cheers

Mark

put candles in the coils and enjoy them in the garden

pad

Thanks Pad - so you won't want to know when they go on E-bay then!!!

Erm - no its ok , but thanks for asking

pad

Even greater reason for not fitting coil spring suspension - its an absolute pain swapping it all back to rubber donuts! Particularly the front radiator side. Needed to take the top arm out!! A tricky job with nice fresh paintwork you don't want to scratch!!

Two down - two to go

Most I have installed I did not care for, but I did like the Delta Mini ones that I had on a driver a few years back. They were a combination of 2 springs and had little rubber bits between all of them to keep things from squeaking/rattling, along with stiff KAD sway bars it was a blast to drive.

I haven't run springs, but done a lot of research in to the possibility of fitting them to a Mini over the years.

For record, and the most part, I like many of the up-sides of conventional springs, in particular the lack of need to replace them every few years.

However, spring steel technology just can't replace or come within a bull's roar or replicating the rubber cone / trumpet set up that the Mini has. One Spring Engineer even asked me after working with him for a few months "ever though of using rubber?"

I've tested a number of rubber cones and a few coil springs in the workshop for data, measured at the knuckle joint, from re-bound stop to 50% compression of the bump stop (on the fronts) the 'spring' (what ever form it maybe) needs to have 53 mm of travel + 9 mm of pre-compression (although this will depend on rate and static ride height).

Rubber Cones (even the Mini Spares Red Spot ones) can easy do this and more, yet the best coil spring that I've tested had only 38 mm before Coil Bind. The rate is also linear with a coil spring, where as with a rubber cone / trumpet set up, it's progressive.

Try as they might, they just aren't there.