I'm going to put coilovers on my coupe and need to know what the average clearance people are running between the top arm and the bump stop. Basically i'm going to cant the coilovers inwards as on the hillclimb coupe to try and get some rising rate. This dimension will help me get the top mount in the right place for compression/droop

Should you continue to use the existing bump stop - As far as I'm aware, suspension designed for coilovers use them of exactly the right height and use a bump stop rubber on the shaft.

I don't know the answer

I do'nt intend to use the original bump stop, it's just for a reference measurement as my car is on axle stands at the moment. I intend to set the coilovers so the internal bumpstops will allow the suspension to compress a bit more than the original Mini setup (some people cut Mini bumpstops down)

My clearance between top arm and uncur bumpstop is about one digit from memory



WEST

You'll find that the original bumpstop will get in the way, even when we were racing minis we shortened this, I have done away with mine all together and use the one on the coilover, I found that to get a good look round the wheel arches the original was preventing it from lowering further, I'm not talking heaps here as you don't want excessive angle on the top balljoint as it won't cope and will break. I recken mine is about 15mm shorter than factory and when the bump was there it had about 15mm clearence.

I'll be interested to see how you get on. It's difficult to get enough lean on the dampers of a Mini to get rising rate. The damn things actually lean totally the wrong way as a standard fitment.



With a spring wrapped round them you have even less room. That's one of the reasons I went to rocker arms on my Coupe. I managed to get a small amount of rising rate that way.

John, Yes i know they lean the wrong way as standard Have a look at the way the coilovers are mounted on Dermots hillclimb coupe. They would have to be 1.9" units, but i've already cut my subframe up so a bit more would'nt hurt Doing this would also tackle the weak top mount on the rear. What do you think
viewtopic.php?f=11&t=206

Where are they mounted on the top arm?

The normal coilover conversions don't use the original damper pin as it's not up to the job. They use brackets which mount above the arm on the damper pin and the ball joint nut but that would move the dampers too far back wouldn't it? That's why I'm interested in seeing how it works out.

On Dermot's car they appear to be mounted in the standard position, weather the top arms are standard i could'nt say but they certainly look like it.

Guys,

I've got coilovers on mine, I haven't hacked apart the subframe and by modifying the top and bottom mounts I have got it perpendicular, ie straight up and down. You are right the top mount isn't up to the job and does need some extra stengthening, the bottom mount was moved towards the balljoint but does not extend into the ball joint as I found it fouled the wheel. I'm using AVO 1.9 with 180lb springs, started with 225lb but was too stiff for the road they also use 1/2" eyes so you need to upgrade these from the 3/8 originals. The rears are the same however the top mount is still the same position as the original but just stronger, the rears are point in slightly say 15mm but it doesn't seem to effect it and minis always had inward facing shocks, I'm using 250lb on the back and it seems to be ok. I have been thinking of fabricating longer top arms so that I can get the shock angle better, (seems to be a standard mod on minis running coilovers). The only prob I've found is that it does rub slightly on full lock but I haven't chossen my wheels yet and my change the offset to avoid this.

I reckon, using standard lower mounting points, standard ride height and standard length dampers, that you would need to move the top mounting point in by about 70mm to get a rising rate on the springs.



Is that similar to what you've worked out Tim?

You won't be able to use the standard bottom mount as it is for one too small 3/8 instead of 1/2" and secondly it will foul on both the subframe top mounting point and also the side of the subframe. You need to move the bottom mount as far out as you can unless you want to hack apart and reconfigure the front frame. I have also spaced mine away from the bottom arm to get clearence also.

John, Andy,
Just under 3" is what i thought too with the standard setup, but from what i can gather the ride height required on the coupe would put the top arm pretty close to the original bump stop tip (i'm not going to use it, its just a reference point ) so that changes things a bit. I'm looking at using 12-12 1/2" coilovers. If slicing a section off the tower is necessery thats fine. On my rear subframe the original side rails are'nt there so that's one thing less to worry about. I'm in the process of making a new bottom coilover mount that will take 1/2" bolt and move the mounting upwards and outwards.

Andy
You can ream the bore in the top arm out to 1/2" if you want to use the mounting point but that leaves the metal around the pin a little thin in my opinion. I took it out to 7/16" on my car but that was for the pushrod rose joint.

John,
I also considered drilling the hole to 1/2" but like you felt that amount of material left would'nt be enough to feel safe, i did think about offset boring it too. I'll see how the new mounts turn out first