No Preload on Springs??

[mrdatto]

Hi All,

I was putting together my new spring/shock combo tonight and found that when it was all assembled there was virtually no preload on the spring at all, and it was free to rotate in the perch. I have Tokico HP Shocks and a set of lowered king springs.

I understand that once installed the weight of the car will load up the spring, but am concerned that if the suspension gets near full travel the spring may dislodge.

Is anyone else running this combo, or is anyone with lowered king or similar springs had any problems? Is there a way to secure the spring into the perch?

Thanks

[260DET]

You say 'virtually no preload' so there is some, even though the spring can be rotated? And you are using the stock spring perch setup?

Sounds like there may be too much suspension droop ie the shocks have too much down travel, pics would be good.

[Brett240]

yep, your shocks have too much travel. you can drill small holes in your spring seats, then cable tie or lock tie the springsto the seats ( not tight, just to stop the springs from being able to sit completely out of the seat).

or you can get shocks with a shorter travel.......

[Mr Camouflage]

THis guy had the same problem

http://www.classiczcars.com/forums/showthread.php?p=110839#post110839

[260DET]

Well spotted Mr C, I've responded to that one as well. Must be because I'm feeling mellow after a few beers

[mrdatto]

Thanks All,

They are just sitting in the perch and arent able to move out vertically, but may twist horizontally. I have lockwired them in so they dont twist.

Damned if I'm getting shocks with less travel, waited ages to get these. But that was more my procrastinating than anything else.

Suspension goes in this week, everything has been either replaced or sandblasted and powder coated, looks great if I may say so myself.

[my_mad_z]

I had the same problem when I lowered my 260Z.... the car use to get airborne over small bumps at high speeds....very scary! I had king springs and standard shocks, mind you the shocks would bottom out all the time, had to replace them every six months. I got a quote to install a decent suspension setup, $2,500-$3,000.... I decided to stick with the setup I had.

I have overcome the problem with the 240z I am restoring at the moment. I took matters into my own hands and decided to modify the suspension. I removed the struts and started cutting; I cut approximately 55mm from the front struts and 60mm from the rear (can't remember exactly). I then welded the threaded sleeve back in place and reinforced it.

The shockers that I have used for the front are actually out of a toyota camry, and they work fantastic! I had to relocate the spring saddle to ensure that there would be a sufficient preload. I used the original 240z front shockers for the rear. The car sits at a very nice ride height and doesn't bottom out. My next step is to install coilovers, but I haven't been able to source them at a reasonable price yet. So until then, I have actually used a cominbation of 240z and 260z stock springs; the king springs were no longer suitable for the application.

A friend of mine has a very similar setup on his Z and I can tell you that the car handles and drives like a dream.

Speed technology in Mitcham do a full suspension setup, making everything adjustable, however it comes at a price.

[Murph]

Similar setup here, kings lowered and KYB shocks. My fronts trap just, but the rears are borderline. The springs can move around a little, but not enough that they can fall off the perch. In 13 months of hard driving I've never had a problem, had them twist or fall off. Will be interesting to see what they say if it ever gets sent over the pits at QT.

[xray]

wait a sec...

let me get this straight. In order to use "performance" springs on a 240z, you should cut the strut assemblies? I just checked the MSA website, along with Tokico's website and their install guide (I just bought the ILK-252 set), and nowhere does it mention irreversible alteration of such a key component! After all, aren't the strut cartridges designed to sit within a normal length strut tube, and wouldn't cutting the tube just expose the top two inches of cartridge?

I would think that a performance suspension package that is designed for the 240 would have taken into account such things as preload, travel, etc. Now (along with he thread Mr. C mentioned above) I am a bit worried I wasted some money on those springs.....

Ugh.

X

[Walter Moore]

No, not the actual STRUT assembly itself.

The installed spring length is controlled by the length of the ROD in the SHOCK insert. (The replaceable part)

what my_mad_z did was to shorten this rod by cutting it an rewelding the threaded part back on to the remainder.

(Which would scare me. I have seen too many welds break. But then, he is the one driving it...)

In any event, if you intend to use shorter than standard springs, then you really need strut inserts with a shorter than standard rod. (At least that is what I think is being said here.)

[Murph]

No, not the actual STRUT assembly itself.

The installed spring length is controlled by the length of the ROD in the SHOCK insert. (The replaceable part)

what my_mad_z did was to shorten this rod by cutting it an rewelding the threaded part back on to the remainder.

Walter, you sure that's what he means? I doubt it. If he did, that would be impossible to retain anywhere near the original strength. It'd be pretty damn silly.

[Walter Moore]

Sorry,

I did misread that post... he actually cut the strut tube, welded it back together shorter, and then used shorter shock inserts.... from a Toyota.

Still not a good idea. In either case that weld is subjected to either the full preload force of the spring, or the full weight of one corner of the car, depending upon whether the cut was made above the lower spring support or below it. (Not to mention that the next owner of the car may end up having to buy (4) $600 strut housings if he wants to make the ride height original.)

If all you want to do is install shock inserts with shorter rods, wouldn't it be easier (and safter) to insert spacers under the new shock body in the existing tube to take up the empty space? I mean all you would have to do is find some bar stock, or thick walled tubing of the correct diameter and cut it to the length you needed.

But here is the real answer to the question. Call whomever it was that sold you the springs and ASK them what to do about the incorrect spring tension. They might even have strut inserts that have the correct length rod to make the springs work.