Coil-over Shockers And Springs

[Guest hypermick]

Hi Guys,.

 

I'm doing some further research into shockers and springs. Im particularly interested in anyone who has had problems, not for instance just with Zimmers (though these seems to raise the biggest problems) but with any set up.

 

It would be really useful if I could have some input from those of you who have had problems, particularly with units which, after a small amount of mileage have damaged or distorted the bushes.

 

If possible could you say :

 

What shocker set up youre currently using,. ie, MAKE, SPRING RATING (front & rear), and most important the LENGTH (open and closed of front and rear units).

 

I'm particularly interested in the SETTLED LENGTH of the shockers. This is a really important part of the research Im carrying out. Just to clarify, the settled length is that with the car standing on flat ground, (preferably with the handbrake off) and a measurement taken between the top and bottom shocker eye centres.

 

All input greatfully appreciated, since I need to compile it, and take the research from there.

 

The more info I get, hopefully it will help us all at the end, when I come to write up the findings.

 

thanks

 

Mick

[Grim]

I wont say a make (because it's common to all of them) but if you have too soft springs causing them to hit the bump stops, you'll knacker them, as i found to my cost.

 

You can calculate the settled length of your shockers, if you know the geometry, spring rate, weight of the car, and preload distance on spring.

 

Why do you want to know all this? What do you aim to find out?

[Guest salty_monk]

What units at what size with what spring rate I would think....

 

I have the older Zimmers front, Sierra rear. 4,500 miles, no probs so far.

 

Dan

[Guest hypermick]

Hi Guys,.

 

I think I need to clarify a couple of points, just quickly.

 

The information I need isn't calculated information. Its the information from your existing set up I need.

 

All you have to do is measure (with the car sitting on flat ground, handbrake off) the distance between the the shocker eyes, front and rear (where coilovers are fitted all round only). It doesnt apply to sliding pillar fronts and sierra struts used upside down on the rear with seperate shockers.

 

Add to those measurements, the spring ratings youre using, front and rear please and also the open and closed lengths of the shockers, again front and rear.

 

From that information I can work from there and hopefully help with problems, not just for my benefit but more so for others who have previously had coil binding and prematurely worn out bushes,. photos of which have been posted a number of times on the forum on a number of occasions.

 

Ive looked closely at this subject due to the differing accounts people have given on their suspension. Im particularly concerned about the damage on the bushes and the aspect of coil binding when I know from experience that this should not be happening.

 

I'm currently talking with one or two manufacturers too.

 

Please, when you post information, make sure its as accurate as possible since this will affect the end results when the information is compiled.

 

Grim,. where on your suspension are you using bumpstops ?

 

Thanks again to all who can participate.

 

 

 

Mick.

[Grim]

They're in place in the front and coilovers (although they don't do anything as the coilover is a touch long). AFAIK all coilovers come with them.

[Guest chris brown]

AFAIK all coilovers come with them.

Well mine have as well

[Guest salty_monk]

Mick,

 

Style of suspension will play a big difference. The series 3's with the onboard coilover's use a lot lower spring rates than the 2b's. The superspec should be similar to the 2b but the engines & car weights will be slightly different...

 

Just a few thoughts.

 

I think you probably only want the info for 2b's but please clarify.

 

Dan

[Guest elwe]

Last week a technical guy at Robin Hood told me the superspec was heavier than a 2B and so fitted with higher rate springs. He then asked if the springs on the superspec shockers I have for my 2nd 2B were blue, This would indicate the higher rate.

[Guest hypermick]

Dan,. The info is for the 2B's yes. Coil overs front and rear, wishbone front suspension.

 

I'm getting the impression that many of the owners on here are treating this as a hit and miss part of the build. I could be wrong and apologise in advance for that, but Im truly not satisfied with the gross missmash of suspension interpretations Ive seen.

 

On numerous occasions people complain of excessive coil binding. This could be a due to a bad choice of springs, the wrong number of coil turns for the given length, worsened by over compression on too short a shocker body. Theres also evidence that many people are using springs that are far too strong and not allowing the shox to operate in the way they were designed to. Im not sure where the idea comes from that the stronger the spring the better it will be but according to the manufacturers Ive spoken to they say that generally speaking, given a typical cars make up, once established, there should be little variation in the parts and the rest should be down to personal settings made only by shocker adjustment.

 

The aspect of the Zimmers being hammered to bits on the bushes is absolutely crazy, and it may be that the shockers themselves are quite usable but being used in slightly the wrong position on the set up, especially the fronts.

 

As a matter of interest there is a settled length measurement, which is determined by the open and closed length of the shocker. If the information Ive asked for is put on here it will be facinating to see the variations. I can tell you what it should be, but that would completely defeat the object of the exercise and make the input less valuable since there may be the odd builder who measures the set up and finds that his measurements arent what they should be, then,.......................................well you know,...........embarrasment factor !!!.

 

SO,.....................to save face if anyone wants to PM me with their info please feel free to do so and I'll keep it just for the statistics table.

 

I treat suspension very seriously. Incorrectly set up the car may seem fine to drive around till the cows come home. Its only when you have an instance of emergency that you realise that the suspension cant deal with the road condition then,,,,,,,,,its big trouble.

 

I really do need all the measurement information please, that Ive asked for, even if your set up seems to work well for you. Even better if you are completely pleased with it,. do still make the posting then I can compare the good set ups with those folks have had problems.

 

Once Ive got sufficient info I'll do my best to work out the best configurations, having looked at the manufacturers input and recommendations.

 

Ive had a selection of GAZ units delivered today and will be noting the differences they make, for given operational length etc,. etc. and Ive chosen one spring rating as a starting point, so I can work from there.

Its the old merit that even NO tells you something , but not contributing tells me nothing, and the question of springs and shockers problem will remain unless its properly looked into.

 

 

Guys, if you want to post on this thread, on this occasion please keep it only to the info Ive asked for, it really will help, not going off at a tangent with general comments about shockers.

If youre running anything that hasnt got wishbones and coil overs front and rear, sorry Im not on the case on this occasion.

 

 

thanks

 

Mick.

[Guest klaxon]

Hi Mick

I've just chnged my Zimmers for Gaz......Big improvement.

I'll pm you with more info.

Here's the basics.

Car.......2B wishbone....weight - 780 kgs.

Front 14" unit 325lb x 8" spring Settled length 12.25"

Rear 17" unit 300lb x 10" spring Settled length 15.25"

Having trouble with sqeak on rear unit. Gets worse if unit is adjusted to be firmer.

[Guest timswait]

Having trouble with sqeak on rear unit

More likely to be the bearing at one end or the other than the damper itself, Grim has this problem with his (although he's using spherical bearings for some reason...)

Sorry to digress

[Guest hypermick]

Ron,. sorry read the PM but didnt read the board reply first, which youve given more info on.

 

 

Mick

[Joel]

Having trouble with sqeak on rear unit.

 

I swapped my zimmers for Gaz all round a couple of weeks ago, and pretty much as everyone else says - big improvement and very pleased with them, but I also have the infuriating squeek from the rears, which no amount fo WD40 seems to fix!

So if anyone comes up with a definative solution I'd be eternally grateful to hear it.

 

Getting back on topic - I had the standard '2B kit' from Dampertech, which wasn't quite as straight a swap as I'd hoped. No criticism of Dampertech, they were very prompt and professional, but I guess a 'universal' kit is never going to fit like a custom one. Nothing major, I just had to spend a long time adjusting brackets and things, mainly the top rear roll-bar bracket, which I'd never intended to be moved.

 

Also I would have had longer springs all round if I'd realised, because I've had to wind them up a good distance to get a half decent ride height. And upgrading to 325 (I think?) on the front was definately a good move.

 

Just a few things to consider for anyone going down that route.

[Guest salty_monk]

Squeaks could be caused by misalignment.....

 

[Joel]

Squeaks could be caused by misalignment.....

 

Misalignment in what, where, how exactly?

 

Interestingly, no matter how enthusiastically I bounce on the back of car, I can never recreate the squeek at stand-still, only when I'm driving. But it certainly never did it before the new shocks were fitted.