Fitting YJ springs to a Samurai

[dan_2k_uk]

I might still be interested but need to make brackets and flex it up first to check lengths.

[Ladaman]

Well I think I've got the rear end loosely roughed out. Again feel free to comment, but after lots of changing things around, I seem to have ended up with this.

I've tried moving the spring forward about another 60mm I think it was, but the "clamp" around the springs fouled the bracket. I tried the YJ's on the rear end. I tried the Navara springs with the longer half forwards, and many other combinations, but I think this seems about the best (unless you can think of some thing else).
I've got the Navara spring mounted the "wrong" way around (small eye to the front) in the hole I originally drilled. This puts the axle about 65mm further back, So I've drilled some additional holes in the plates tack welded to the axle 30mm back pushing the axle forward that amount. I also made some shorter missing links at 75mm centers to sort out the shackle angle.
On a bounce test the Navara and YJ's seem very similar, so should be OK.

It's all very temporary at the moment, but I thought I'd show you where I've got to.

There will be a few additional mods to do to allow the 31's to go on, as I've now tried them and they foul on the bumper, so mods to that and probably a virtual lift will be needed.

Oh the joys.......

[Anton]

Exploring new territory always has it's unexpected pitfalls, but I think you've done a brilliant job.

You might have issues with flex having the small eye facing forward on the Navara spring, though - the small bush will limit the amount of rotation the spring will allow, limiting flex. Normally there are two small bushes one end (either end of the shackle) and a dirty great big one the other end. The doubling up offers more flex.

Since you've moved yours to the chassis end, you may find you've halved the amount of rotational flex available to the spring, which could cause it to bind and stop the spring articulating as much as it otherwise should.

Because of that, might I suggest you think about a shackle reversal on the back?

That comes with it's own set of problems, though.

Still, awesome job so far! You certainly don't seem to be worried about forging a new path for us to follow!

[Ladaman]

Mmmmm Anton, you got me thinking on that one, I must admit I hadn't considered it.

So it was time for a bit of experimenting this morning. To check how much articulation was possible I tied the axle to the chassis at one side and lifted the whole back end up by the tow point

What a bummer, only about 3" lift before the other wheel lifted. Remember this is only free weight pulling the axle down. It goes much further when blocked up and weight on it.

Springs off yet again, turned around so the big eye is at the front as it should be. Similar result

Swapped them out for the YJ's, a bit better, but the front bushes are shot, so that is probably why it was better.

So the conclusion was, fcuk it, this is only a prototype. Let's see how it performs for real.

All the rear end is now off and painted, ready for reassembly again tomorrow.

It has got me thinking how crap having bushes is at the front of the springs. Is there something else that can be fitted like a rose joint to allow the spring to rotate, but be stiff front to back?

[Anton]

Just a couple of things I thought about myself - the second one would be very simple to do both ends of the spring (on the "big" end, that has no shackle, you'd make it so it sat square against the chassis, and therefore would only allow rotation left/right, not forward/backwards too).

It would lift the truck by an inch or two though. And I'm not sure you want that...

I wouldn't try combining them though, as one could shift left, the other shift right, and that would allow the whole axle to move laterally.

Adding a triangulated wishbone upper link (like a vitara has on the rear) or a panhard rod should get rid of that problem.

But getting rid of bushes has another downside - increased road noise due to vibrations being transferred up the spring and into the chassis...

Here's a look at a shock mount version of the second idea:



Imagine that, but big enough to fit bushes into. Big enough to fit your springs, rather than your shocks.

Now imagine that the centremost set have a piece of box section welded to them, so that when they're put in place, they're flat against the chassis - and can't move forward/backward, only rotate left/right...

[ScottieJ]

Ladaman to me it sounds like the way you are trying to test the flex is why it's not showing the actual flex you will get, you either need to jack the back end up directly under one of the tyres or use and engine hoist to lift one side.

[Jordi]

If you can try flex opposite corners up as much as possible at the same time.

[Ladaman]

More food for thought.

Anton, I really like the first idea, I might be able to make something like those. Do you have a link to where you got the pic from. I'm sure I can sort something if not.

Scottie, I know there is much more flex there, and when I have the YJ's on the front I will check it out. My point was how solid it all seems with only the axle weight pulling it down. I was hoping for it to articulate under free weight easier than that. Maybe that's how it is, unless I knock up some of the mounts Antons pointed out.

Jordi, As above I will see what I can do when I've got the front done also.

In the meantime I will just carry on and bolt the back end up tomorrow, and then try to turn it around in the garage to start on the front end.

As for road noise, who cares? On the last laning trip I did (video still to do) I fitted my old rally intercom head sets for the road sections.

[Jordi]

Road noise? My tyres are silent. In fact my whole Zuk is so quiet it's registered as stealth.

[Anton]

More food for thought.

Anton, I really like the first idea, I might be able to make something like those. Do you have a link to where you got the pic from. I'm sure I can sort something if not.

Nope, sorry - I found the pic a while ago on google images. Can't even find it again now, although searching for "orbit eye leaf spring" came up with the following:

http://www.alcanspring.com/orbit-eye.htm



If you can make these work both ends of a navara spring, you might just have a YJ beater!

That is, until someone fits a set to YJ's...