Superspec Front Suspension

[alanrichey]

Sorry, this is now confusing the hell out of me. I thought I understood the physics behind this but apparently not I need to watch someone actually doing it before I feel confident to do it myself.

[Graham B]

After nending my lower wishbones. i had to yhink sgain. My solution was to keep the most outboard mounting point , but fit longer shocks. Mine were assembled for me at Protech In Melksham. Exactly the length I wanted.

[alanrichey]

Sounds expensive ?

[stevedohc2b]

I think I have a home made spanner that you could have if you want to pay postage

Stephen

[agent_zed]

ok so one of two things might happen.

 

1. Your shock stops the wishbones dropping any further. In this case undoing the shock bolts should allow the wishbones to drop more and the shock to come free.

 

2. Your shock is mounted further in/or so long, that even at full droop the shock is not fully extended and some pressure remains on the shock as the balljoints are at full travel and are now the end point. You would therefore need to compress the shock to get it off. As said winding the spring out should reduce the pressure on the shock and you might be able to move it enough by hand to get it out.

 

 

What i would do is jack it up as said until the wheel starts to lift, loosen the shock bolts a little and then jack a little more. Now take the shock and give it a pull back and forth and see if is loose or still has pressure from the spring. If you have spring pressure you'll have to compress it.

 

hopefully you have number 1 so it just comes away easily.

 

Hope that makes sense

[alanrichey]

What i would do is jack it up as said until the wheel starts to lift, loosen the shock bolts a little and then jack a little more. Now take the shock and give it a pull back and forth and see if is loose or still has pressure from the spring. If you have spring pressure you'll have to compress it.

That's exactly what I did and even with the nuts removed the shock was still rock solid when the wheel wouild 'just' rotate by hand. So as you say, I probably need to compress it. The part of the 'physics' I was missing/didn't understand was that the wheel/wishbone might start rising because the balljoints have reached the limit. That makes a lot of sense, thanks.

[alanrichey]

I think I have a home made spanner that you could have if you want to pay postage

Thanks, I'll bear that in mind.

[edbond]

Afraid I don't have a 60mm spanner. I was hoping I wouldn't need it, I obviously do. Although surely the shock is already at full length at the point where the tyre/wishbone starts to come off the floor ? Otherwise it would keep extending.

 

I brought one of these to wind up my nuts on my zimmers

 

http://www.toolstation.com/shop/Hand%20Tools/Plumbers%20Tools/Superwide%20Jaws%20Adjustable%20Wrench/d10/sd210/p13892

 

Gave me about 2cm more clearance

[alanrichey]

Looks good. How far up did you wind them up ?

[edbond]

Looks good. How far up did you wind them up ?

 

Just a bit!

 

 

[edbond]

 

 

Just a bit!

[alanrichey]

Thanks, that's very useful as a comparison. I am using the same mounting hole as you but have hardly any of the coil thread showing. I was planning on moving it in one more hole closer to the chassis. Maybe I should just wind them up a bit.

[alanrichey]

Just to close out this thread, I've done it !! I know this is bread & butter for most of you, but it's a first for me so I am quite chuffed, another step along the learning curve I took all the advice here and from all the contacts at Hollowell (particularly Kerry) and didn't move the lower mounting point. I got the tool recommended by Ed and wound the spring up to match his picture. Sump clearance has gone from 2" to 3.5". That may very well be enough, but I shall watch over the next few drives to make sure I don't get coli-bound and see if I can get away with a bit more. It's handy that you can actually see the springs in a Robin Hood

 

I made the mistake of not checking the camber before I started, but once the springs were wound up I am getting -1.0° on the offside and +0.7° on the nearside, so I am guessing they probably weren't correct before. From what I have read this will be safe, but it would be better to get the nearside a bit on the -ve side ? A job for next week.

 

So thanks again for all the advice and help.

[agent_zed]

Hi,

you should be able to adjust the camber using the top balljoint.

 

I'm not sure you've got in looking around the suspension so i'll start from the begining.

 

The RH with the standard RH wishbone suspension uses (as you know) the hub from a sierra. This has a big hole where the mcpherson strut should be so to solve this a 'dummy strut' or 'mushroom' is used. The top balljoint then goes into a tapered hole in the dummy strut and is bolted with a nut on the inside. This nut is quite hard to get to when its all on the car.

 

The dummy strut is then inserted into the hub and the pinchbolt holds it in place just like it would with a mcpherson. Something you may wish to check - the mcpherson has a wing out the back which has a hole in it which sits in the slot for the pinch bolt so the bolt passes through. If the pinch bolt comes loose the strut cannot come out (assuming the bolt doesn't slide completely out). This is not on the dummy strut so it is possible if the pinch bolt comes loose for the dummy strut to slide out (it has happened to at least one member on here thankfully in a carpark not at speed). A simple fix for this is to drill a hole through the side of the hub and strut and but a bolt or roll pin through.

 

Camber and the RH problem

So RH managed to mess up the geometry somehow as the mount for the top wishbone is too high so the top wishbone slopes downwards towards the wheel. This means as the suspension rises the top of the wheel is pushed out and gives + camber! which it shouldn't do. Have a look at caterham suspension on google images and you'll see the top wishbone is at the very least parrallel with the bottom wishbone or higher at the wheel end.

To solve this some people fit longer dummy struts which raises the wheel end of the wishbone. This should then give you more - camber as the suspension rises.

 

How to adjust the camber

the top balljoint screws into the wishbone. If you jack the car up so the weight is off the spring then undo the pinch bolt and drift out the dummy strut (still all connected to the balljoint/wishbone) you can then turn the entire thing round and either screw in for more negative or screw out for more positive camber. You don't get much adjustment though as it will be a complete turn.

 

If you put the car on glossy magazines first when you lower the car down it should allow a bit of slip and get the wheels back to the natural position.

 

 

HTH

[Guest Ian & Carole]

Alan

Once you are happy with your ride height if you do discover that you are getting coil bound it might be worth going up 50 lbs on your springs. It will retain the height you want and release some spring space, if that makes sense.

I had to do this with mine after I did the wish bone conversion.

By the way it was my dummy strut that fell out in a fuel station on the A1 a week after we had been to Germany and done a lap of the " ring" how lucky we're we.

2 x 3 mm roll pins now installed.

HTHs

http://s44.photobucket.com/user/IJMJ1/media/Image021.jpg.html?sort=6&o=75