Z coilover options

twoforty

twoforty

Well-Known Forum User
After spending a lot of time reading about fitting coil overs on a 240 I have finally found a pretty good solution. Fitting 2 1/4 springs directly over the original strut.
I have found a guy that will cut the original struts down in length and without cutting the tube from the hub, mount the whole thing in a lathe and turn a thread down the whole length of the strut. He is also making locking collars to fit.
Also a local company to me called Protech shocks limited make fully adjustable inserts to fit shortened 240 struts at a very reasonable price.
If anyone is planning on lowering/ modifying thier suspension email me for full details.
Cheers
 
One bad thing about this method is that the area at the top end of the strut tube will become very weak due to the internal thread for the gland nut that holds the shock insert in place. Be very careful and think hard about going down this route, I've already scrapped off a similar design idea for this very reason and I'm using CDS tubing, not 30 year old rusted Datsun steel.

Cheers,
Rob
 
Hi rob
Yes I thought about that also, the inserts are sealed and only need oil around them for cooloing so the top doesn't need to be air tight. The inserts are also a smaller diameter so I small insert can be fitted in the top and new tops are also being made. I forgot to mention that :)
Hopefully it will all be ok, the guy is proper old school!
Will post some pics in a week when its all done
Cheers
 
turn a thread down the whole length of the strut
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Whoaa there, this is very risky indeed, the wall thickness would be seriously compromised by cutting a thread into the stut tube,

Lowering and fitting coil overs is nothing new and there are numerous Z cars with this set up, You must be seriously lowering your car if your going down the route of removing material from your strut.

So why not use the tried and tested method that everyone else uses, weld on threaded sleeve to the right point (can be bought as complete kits with spring perches and lock rings) also why not use the same shocks that people have used in the past such as Tokiko Blues or illumina's (adjustable) or the tried and tested inserts for shortened tubes (call Mike at MJP he'll tell you which ones) once again these are tried and tested methods, no "wallet experimentation" needed
 
Steve
No wallet excuses here, thats the last of my problems:) There is plenty of metal in the strut and as for the top part with the shock retainer, the only stress here is from hold the shock in place,. The load is on the platform and below, the thread is very fine with steel collars. I will hammer it round the track to test it. If I end up with 3 wheels on my wagon please don't say I told you so:D
I wasn't trying to suggest that noone else had thought of coilover just wanted to give a heads up to people that had maybe not considered this route.
There are probably many unsafe Z's on the road, soft bushes, bad brakes, rusted chassis, shot dampers, lap seat belts to name a few things.
 
Not a Zed strut I know, but this seems the norm
Grind the weld from the original spring platform and reweld a threaded tube in its place, add extra bracing if you wish too.



mush2.jpg


mush1.jpg
 
Nice photos 900ss, I will add some extra support at the bottom for good measure. Oooo er!!:p
 
Twoforty -- If you thread the strut with a metric thread, its "root" (correct terminology) will cut into the strut buy at least 1 mm thats 1 mm less material you have holding your wheels on with as the standard Z strut has a wall thickness of about 4mm. So by cutting a thread along its length you are taking a 1/4 of its strength out -- fact, where as putting on a threaded collar will increase the strength of the strut -- fact.

There are probably many unsafe Z's on the road, soft bushes, bad brakes, rusted chassis, shot dampers, lap seat belts to name a few things.
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Agreed but all of these faults are through general wear and tear/age, not deliberate attempts to commit suicide, its like deliberately not using all of your wheel nuts, in order to save weight.

and as for the top part with the shock retainer, the only stress here is from hold the shock in place
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Not true -- when in a rapid spring unload situation such as going over a bridge at speed, momentarily the threaded section and gland nut will take weight as the damper tries to draw out of the tube.

If I end up with 3 wheels on my wagon please don't say I told you so:D
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If we do lets hope it wont be via a seance:( .

My comment
"wallet experimentation"
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was refering to the fact that its often better to use tried and tested routes rather that break new ground at your own expense, it wasnt any referance to your own personal financial situation.
 
Point taken but I will leave it to the guy doing the job to test the strength after its finished. I'm sure a factor of safety was built in from the start.
As for the top nut taking the stress going over a bridge, I would have to get the wheels off the ground or close to it and the worst that could happen is the damper could come out, the springs fall off its perch and the wheel collapse under the arch!:eek: lol
I'm not sure if the guy is using a metric thread or not as he is also making the adjustment rings. I will ask him later and also point out the strength problem.
There was I thinking you had made a spelling mistake, "Seance" :) I will give 3 knocks for yes!
 
Am I right in assuming the whole strut will be threaded (it would have to be) and the top nut keeping the damper in will be fixed with that same external thread ?
 
I was thinking you might just as well sleeve it with a tube on the outside, no more cost or work but obviously safer? Or is there something preventing that?
 
Guys you can stop ya worrying, I took my springs round to the chap who is doing the work last night; He already checked the thickness of the tube, decided they were too thin, bored them out of the hubs and is replacing with thicker section tube, making collars, shock retainers and new top spring plates for £35
 
It sounds an interesting option, please keep us updated with progress and some photos of the finished product.
 
Will do, I know everyone thinks the slip on threaded tube is a better option but this way I can change spring lengths/ride height without too much problem; and its also a lot cleaner especially in S Steel
 
It will certainly look cleaner if nothing else.
If it's not too late, have you considered using late 260Z stub axels ? There is more meat to them and larger in diameter.
 
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