Outer Limits 4x4 Board

What do you guys reckon of these? Theyre designed for drag cars, but have much the same principle we're chasing.

www.sjperformance.com.au - I've spoken to the owner and he seems to be dead sure this system wont limit flex... check the articles on his site (PDF files) they show pretty good pics of how it works.

Basically its an arm below each leaf going in the direction of the driveshaft from under the u-bolt and joining below the spring hanger (its a bolt-on system that replaces the bush in the hanger end of the leaf).

I think its a very viable option - perhaps a very good solution to what we've been seeing so far... my only concern is that on compression and extension of the leaf, the leaf gets shorter as it arcs, and the arm has no give for that... be interesting to see what you all think about it...

be good to see people using bonded bushes.

Unless I'm misinterpreting the pics the device mounts underneath the spring ?

Not good for ground clearance if so.

yes, it does mount below the spring, however it mounts right next to the rim and doesnt go below the rim, so ground clearance isnt really affected, as anything running in that area is going to be hitting the tyre, not the hanger.

You could tuck the hanger up higher but the triangle of the bar would be less and it'd have less effect on reducing wrap.

It looks like a well planned out product but probably designed more for cars with limited need of flex range like a 4WD...? I think the issue might be is that the people that would really need this to deal with axle wrap are the SPOA Sierras where as the SUA doesn't really have to deal with axle wrap....?

alien wrote:yes, it does mount below the spring, however it mounts right next to the rim and doesnt go below the rim, so ground clearance isnt really affected, as anything running in that area is going to be hitting the tyre, not the hanger.

You could tuck the hanger up higher but the triangle of the bar would be less and it'd have less effect on reducing wrap.

Drive some rutted tracks and check your U bolts and you'll see how much they actually do hit. especially if you're follow Patrols and Cruisers on 35's

im SPOA so the ubolts are upside down... i do know what you mean, but a system like this that is stronger and doesnt limit flex, but might perhaps scrape the ground on occasion, versus a system thats prone to limiting flex or ripping itself apart, but is well clearanced... i dunno, i'd be taking the stronger option...

interesting opinions though... and you're right, its designed for drag cars which generally have very little spring movement, and while i've given flex/travel figures to the manufacturer he still claims his bars will have no effect on articulation.

What is everyones thoughts on those claims? (after seeing the pics)

Obviously the groud clearance thing is a massive problem with these IMHO, but there's another couple of problems I can see.

These are designed as a drag race product, and as such, come into play when the suspension is compressed on launch. In a situation where the suspension is articulated under power, they won't work as well.

They work by loading a bolt against the spring. If the bolt isn't loaded against the spring when power is applied, there's going to be all sorts of nasty banging and slapping.

In a SPOA application, there will be alarge distance between the bar mount under the axle and the spring hanger. The steeper this angle, the less effective the bars will be (and harder to set up)

I think they're an excellent solution for a drag car, but not applicable to an off road car, especially a SPOA one.

Just my 2C.

Steve.

Mate, you only looked at that image on the front page didnt you? =) Its not a slap bar system... its a solid bar that joins the diff to the chassis with pivots at each end. In that image, the end not attached to the rod joins a hanger.

Check out these pics:
http://www.sjperformance.com.au/perform ... au_pg1.pdf

http://www.sjperformance.com.au/perform ... au_pg2.pdf

Ground clearance isnt much worse in that area than when the leaves were SPUA... i would think it'd be a pretty fair trade off compared to busted driveshafts, unis and wrapped leaves.

Given the engineering that goes int their other products and their unquestionable devotion to all things suzuki. I would look at the Spidertrax option.
http://www.spidertrax.com/s.nl/it.A/id.2330/.f

alien wrote:Mate, you only looked at that image on the front page didnt you? =) Its not a slap bar system... its a solid bar that joins the diff to the chassis with pivots at each end. In that image, the end not attached to the rod joins a hanger.

Yes, I looked at the photos at some length. The bar is pushed forwards under power, which rolls the triangular hanger bracket, forcing the bolt which sits above the spring down against the spring. No, it's not a slap bar.

All of my comments stand. I think it is an excellent drag race product that's badly suited to an off road environment.

Steve.

I think and OZ-trac style bar might work with the plate running off the top of the axle and the spring hanger attached to the shackle end of the spring- the whole thing would be kind of inverted.

This would fix the ground clearance problem clearance between the axle and the chassis at full compression to clear the bar, so bumpstop spacing and relocation would be required.

Steve

How does the spidertrax one work? any pics of it in action?

It's just a straight bar with heims at each end.

Steve.

how does it mount though? and where? I've got a serious lack of space above my diff housing due to my shock arrangement... lol

Within limits it looks like it's up to you where it's mounted - have a look at the kit on the site - there's going to be a fair amount of latitude there.

straight bar traction bars, especially on SPOA cars just don't work that well - they always put some bias into the srpings. That's why there's heaps of more complicated designs.

From a quick look they look similar to adens? AZZOOK red soft top with exo. He had one each side to stop wrap. Never tried one but I think this single bar would definatly work better than a over the top single bar, but a triangulated one would work even better.
Nik

NIK - got any pics of his setup or a contact email for him so i can quiz him mate?

The oztraks one goes below both leaves... its a straight rod with heims at each end, and basically makes the driveshaft end of the leaf rigid, other than vertical travel. its literally a bar running below each leaf.

So its basically the same as spidertrax in theory, but theres 1 each side rather than 1 in the middle - so the oztraks one is taking half the load of the spidertrax one, right?

EDIT: heres how the oztraks bar works:

The pic above though at your spring hanger end pivots on another shackle though if your talking about the oztracks one....? Or is this your own design...?

Other issue is for me atleast is your pic does not indicate the angle in which my spring sits, its hard to explain but Ill grab some pics...

no you're right the leaves are angled a bit, i just drew it square to make it easier to draw... the hanger end is not a shackle as such, it just utilises the gap between the spring hanger and the spring to mount itself, and like gwagensteve said, it rests on a bolt against the leaf...

I dont sorry.
It use to be on the cover of GRPs catalog. I think it may have been sold as its been seen twice here in newy area, tried looking for it on here awhile back but got nothing.
Im sure they were very similar to the pic though one each side.
Nik

Oops . I should have added that I don't think any single "bar" will work terribly well in in preventing spring wrap in an off road vehicle.
As for a SPOA setup in a sierra I honestly think that you would be just as well off spending the time and energy getting a 3 or 4 link coil setup sorted, as by the time you start getting reasonable flex it gets very maintenance intensive

love_mud wrote:Oops . I should have added that I don't think any single "bar" will work terribly well in in preventing spring wrap in an off road vehicle.
As for a SPOA setup in a sierra I honestly think that you would be just as well off spending the time and energy getting a 3 or 4 link coil setup sorted, as by the time you start getting reasonable flex it gets very maintenance intensive

+1.

Layto....

You reckon? a trac-bar doesnt need any maintenance (short of the heims failing), and leaves just need the bushes greased every now and then... i've drawn images of this system and it look like it does infact allow full flex without interfering, while stopping wrap...

The issues love_mud were referring to relate to single track bars fixed at both ends like the spider trax bar. The axle path in a leaf sprung vehicle can't be accommodated by a single bar, so bent springs and broken mounts and bars typically result.

His comment in relation to maintenance refers to short spring life with SPOA cars when greater than stock flex is required.

Steve.