Outer Limits 4x4 Board

Hi All,

Just after some details on 3/4 eliptic conversions on a swb widetrack sierra. Has anyone done this?

Current plan of attack is as follows:
1. Move the spring to chassis mount inboard to line up with narrow track specs - the u-bolt mounts will be moved on the axel too.
2. Cut off the shackle / chassis mount.
3. Attach the extra half spring directly above the axel position.

The possible 4th step is to replace the chassis/spring connection with a bollocks or johnny joint or something that swivels a bit to reduce binding at the front end of the spring - the idea being that this should increase the amount that the spring is willing to droop (as it doesn't need to twist) so we get the most droop out of the extra spring length at the back.

Does this look like what i should be after for this application?

http://www.spidertrax.com/fabrication_toy.htm

Or something more like this?

http://www.bigballsoffroad.com/prod480.htm

Liam - perhaps you could comment on this product? Is it going to be able to fit into the existing eye end of an OME spring? What are it's dimensions please.

Any other advise?

Thanks,
Greg

Greg here is a pic that might help
Luigi

an another
LM

The simplest i've seen.
Only hard part is to run gas filler to top of tank, easy if you have a body lift.
Never mind shifting the spring mounts, just weld the angle iron in and remove the rear shackle bracket from frame.
A bolt or two holds the top leafs in place.
Hah! too easy.
Also a pic taken just before he rolled it.
LM

Thanks Luigi,

That setup is pretty close to the setup i was planning. No issues with the fuel tank - my filler is not in the stock posi...

I'm not sure about drilling through the springs and chassis though... All the 3/4 setups i have seen have their springs attached to the chassis with two U bolts and some plate...

Can anyone else comment on drilling through springs? Is that going to weaken them much? Or at least enough for it to be an issue?

Hey Luigi, How much of a problem is binding at the front spring/chassis mount? Is it limiting the travel on the car?

Thanks

It's not my rig, sorry.
But he used two bolts to hold the buggy leaf and appears no probs.
Not sure on the front binding.
I would use a piece of flat and bend a curve into it and use it to hold the front of the buggy leaf. The curve would allow the buggy to move without getting the shearing effect and you wouldn't have to anchor it too tight.
The curved flat piece would limit the front part of the buggy leaf from moving too much at the bolt hole and causing probs ???
That's the theory, now let a genius put us straight.
Oh, if you work it right you won't have to drill the chassis.
LM

Right - now i see what your mate has done - he / she has built a platform for the spring to sit on that runs parallel to the chassis - from the bumpstop (where you now have the 2 bolts attached for the spring) all the way back to where the original mounts were for the rear shackle...

Okay, we are planning something a little bit different which will involve moving the spring so that it sits completely under the chassis rail (as per Narrow Track configurement), this should be a bit more solid, and will also allow us to 'load up' the springs more with the extra leverage to get more travel out of them...

I'm not quite sure what you have described with the curved piece of steel though...

The binding issue that i am concerned with would be the extected twisting of the main spring pack due to the extra travel - this won't be an issue at the shackle end (rear), as the shackle sits quite loose and will flex - allowing the spring to swivel without having to twist. However, as the front is a solid chassis to spring connection - I'm not sure if binding here is going to pose a problem that will limit travel.

does that make sense?

Good luck drilling through the spring you can do it as I have on both my setups but unless you have a good bit it will take hours I ended up doing mine on the mill.
That setup shaown is a basic and easy setup to do.
The best setup is to run a three or four link with shaclkles at bothe ends.
I'll try and find a pic.,
SAM

Yes use a new sharpie bit and lotsa cold water.
The piece of curved steel I refer to is imaginary, but I figure if you make it approx. 75mm to 100mm and weld it at the front end of the angle iron with enough space to fit the buggy leaf in between them, put a downward curve in it and bolt through the lot. Then it would act as a stop for any forward movement and as a downward stop that will limit a shearing action on the leaf, also taking some load from the bolt holes in the leaf. Yeah?
Here is another option.
LM

Ok, I understand the curved steel thing now - it would restrict downward travel of the extra 1/4 leaf... I don't think it's required though.

I don't like the other idea you've shown there because the travel that the "red bit" would provide would not be controlled (as the extra 1/2 eliptic leaf would be), so i expect it would be very loose. See the pic you have attached, it has drooped before the spring pack has even started to move - this suggests that it is not "controlled travel" - which is bad. When you have 3/4 set up, the main spring pack goes to full droop before the extra 1/4 eliptic spring starts to move - that is what you want because it equals more ground pressure and that means more traction and balance for the car.

Yeah I agree with you on the linkage type setup.
What I meant with the curved piece of steel is it will spread the bending of the buggy leaf over a greater radius, and stop it trying to bend at the mounting bolt holes where it is weakest, yes?
I also believe that the main axle spring should work before the buggy leaf does, but this seems to be hard to achieve.
Maybe a lock out pin untill you need the extra, or for off cambers (scary ones) when you could lock the uphill buggy in place ?
LM

What size tyre is that Luigi? It looks like the droop is heaps... Now i can't wait damnit!

Oh, if you are not getting the main spring pack to work, i would suggest that your springs are too hard... This could be fixed by removing some of the load spring from the pack, and also removing the spring clips. However, note that both of these changes will reduce the life of your spring pack.

I believe it's a 31x10.5.

I started to go this way but struck some probs with the A$$ holes doing the work for me.
I ended up fitting revolver shackles and the travel is suffish for now.
But as I have moved the filler to the top of the tank I may do something in the near future. Next time i'll definitely do it myself, wouldn't dream of going back to my local 4WD outfitter, (what a joke they'd be, I shouldda donated the dosh to the brewery)
I may have to make it reversible for warrant checks is all. Shouldn't be too hard now..
LM

here's an idea for the front Greg.
yeah, take that out on the coastal highway.
LM

I've never seen that done before - looks like heaps of flex - i'm just not sure about how well it would all work

However, something else i noticed was the tubbing (new wheel arches) of the rear of that sierra - do you have any more shots of that?

Thanks mate.

ahh yes gimmicks where would we be without them. The Suzuki was never finished from memory because it was way scary to drive. Lots of uncontrolled droop would make it very prone to fall over.

As to those zig zag things they have been prettty well panned by most as again providing impressive looking droop but once again uncontrolled. Flex is overated if all it does is make the wheel drop away with no ground force or traction as a result.

I watched a super slinky flex monster get itself into all sorts of problems at Moab because he was flexed out all over the place with all four wheels spinning away madly because his contact pressure was so low, whilst a stiffer sprung vehicle drove out of the same obstacle. Becuse it was stiffer it picked up a wheel but the remaining 3 on the ground had sufficient contact pressure to give him the traction to move.

I gots to agree with you there Grimbo.
Greg, no pics, I just picked that up on the net one time and saved it for interest sake.
But those wheel tubs are available from US speed shops like Jegs and Summit racing.
Personally I think that getting the wheel to drop 10" or 12" is fine for down under. Getting the tyres and dampening right is of high importance for articulation (read Traction.
In fact, for most off road applications Tyres and Suspension is 90% or more of the deal. How far it moves is not that high on the list.
How the rig is Piloted is quite often the levelling factor.
Heaps of Flex is mainly for the Wow factor.
But what do I know.
LM.

Sorry - back on to this topic again...

Luigi Malone wrote:Heaps of Flex is mainly for the Wow factor.

True, but if the wheels at full droop are still applied to the ground under pressure (i.e. the force of a spring, not just the force of gravity), then the tyre will be more likely to grip, and also the car can still remain balanced.

A quick update on this...

Currently still just in the planning phase... There are a few options being entertained to work out how to get the most out of the mod, and also, how to avoid doing things twice (rather important when someone else is doing the larger part of the welding on your behalf)...

Options:

1. Keep the back completely widetrack - this won't be as elegant as turning the rear into narrow track and will not enable as much leverage to be placed on the springs - so it won't get the maximum amount of travel possible.

2. Turn the back into narrow track - this means that the 1/4 elyptic spring sits flush underneith the chassis, but we will need to modify the position of the u-bolts on the axels, and also move the chassis/spring mount in about 30mm (guestimating). This will also load up the springs and get more articulation.

The third option is acually available to either of the above paths and includes the use of an Orbital Eye in the front end of the rear springs.

See this topic for a discussion:
http://www.outerlimits4x4.com/PHP_Modul ... ght=calbar

The orbital eye will reduce bind in the springs - this will be important in my application because of the swb factor...

The issue here is that the minimum "workable" size of an orbital eye seems to be about 50mm OD x 65mm accross. This (i expect) will not fit into the existing springs (40mm Inner diameter), and will also mean that the existing chassis mount (which i guestimate to be only 50mm + 3mm + 3mm for the bushings = 56mm wide) will need to be replaced with a custom mount that is a bit wider (65mm + bushing requirements)...

In my setup it also looks like the fuel tank will require some "massaging" with a hammer to ease it away from the chassis a little more to allow space for the U-bolts required for the mounting of the 1/4 elyptic spring...

The guestimate is that the new setup will allow an extra 3 to 4 inches of controlled droop (i hope).

have u though about just puttin longer springs in?

the feroza rear springs that i put in flex like crazy

greg wrote:Sorry - back on to this topic again...

Luigi Malone wrote:Heaps of Flex is mainly for the Wow factor.

True, but if the wheels at full droop are still applied to the ground under pressure (i.e. the force of a spring, not just the force of gravity), then the tyre will be more likely to grip, and also the car can still remain balanced.

Two quick thoughts here Greg, 1./ double leafs, well arched as the upside down buggy leaf part. To add down pressure, would need excellent shocks to control bouncing tendencies. Maybe a lockout pin untill needed.

2./ gas shocks to add down pressure. Fox Air or similar,

OK I lied here's #3./ Airbags above the top buggy leafs. With compressor type bags you could control it all from the cab.
As this dude has>>>>>
http://www.bc4x4.com/fv/2000/ben/ben.cfm

Flame me, I don't mind.
LM.

Luigi Malone wrote:double leafs, well arched as the upside down buggy leaf part. To add down pressure, would need excellent shocks to control bouncing tendencies. Maybe a lockout pin untill needed.

Flame me, I don't mind.

I think that because the 1/4 elyptic spring is there by itself, it doesn't require a huge load to keep it flush against the chassis - in fact, the reason that the 1/4 elyptic spring is the last part of the suspension setup to un-load and 'peel' away from the chassis would suggest that just the weight of the vehicle is easily enough to keep it under control.

I have seen a sierra over here that was engineered on the condition that the rear 3/4 setup was 'pinned' for on road use, however, the owner of this vehicle has since ceased using the pin setup because in his opinion it just wasn't required - he was never able to get the 1/4 elyptic spring to unload under on-road conditions...

I think that the air bag setup may be a little more expensive than i was planning.

Sorry mate, I didn't think i'd been flaming you at all. But i guess i can try and start doing so if you want

cheers

redzook wrote:have u though about just puttin longer springs in?

the feroza rear springs that i put in flex like crazy

Okay, now this really has me stumped...

My inital answer was - because it would have to be an extremely long spring to get the same amount of extra travel out of it... But I did a bit of dodgey maths working on the assumptions that a stock rear sierra spring is about 40" eye to eye (although i'm sure OME rears are a bit longer than that), and that the gains of the 3/4 setup would amount to approximately 4"... so a little bit of pythagoras set me up with this formula:

Note: working in half spring lengths:

half new spring length = square root of (old spring length squared)
+ (proposed new travel squared)

half new spring length = square root of (20 x 20) + (4 x 4)
half new spring length = square root of 400 + 16
half new spring length = 20.4

therefore, new spring length would only need to be 41" approximately to match the 3/4 setup...

Note: i realise that this is using straight lines, when springs are curved etc... but i'm siting at my desk at work so hey - what can ya do?

So in theory, your 46" springs should give you a fair bit more droop than a 3/4 setup... Obviously now i am completey crushed and destroyed

However, I can think of a few reasons why 3/4 would be better for my setup:
1. no need to change the drive line lengths
2. my fuel tank filler is already in a new location
3. already have access to springs that can become the 1/4 bit
4. departure angle is not affected - longer springs will mean that your rearmost shackle will be further away from the tyre.
5. rear shock mounts still move in the same arch as before, so no need to move them (thank goodness).
6. my setup will have an extra length of spring that will allow a little more twist - this should reduce bind in the suspension setup...



On another note: One of the fellows in the suzuki club down here is in the development stages of setting up his LWB with a set of hilux rears at the front, and patrol MQ rears at the back - trust me - both of these are very (read VERY) long.. so heaps of flex in anticipated...

We shall see if Steve gets his lwb back on the road. It has been about 4 years or more of serving as a tool chest/spare parts bin

greg wrote:

Luigi Malone wrote:double leafs, well arched as the upside down buggy leaf part. To add down pressure, would need excellent shocks to control bouncing tendencies. Maybe a lockout pin untill needed.

Flame me, I don't mind.

I think that because the 1/4 elyptic spring is there by itself, it doesn't require a huge load to keep it flush against the chassis - in fact, the reason that the 1/4 elyptic spring is the last part of the suspension setup to un-load and 'peel' away from the chassis would suggest that just the weight of the vehicle is easily enough to keep it under control.

I have seen a sierra over here that was engineered on the condition that the rear 3/4 setup was 'pinned' for on road use, however, the owner of this vehicle has since ceased using the pin setup because in his opinion it just wasn't required - he was never able to get the 1/4 elyptic spring to unload under on-road conditions...

I think that the air bag setup may be a little more expensive than i was planning.

Sorry mate, I didn't think i'd been flaming you at all. But i guess i can try and start doing so if you want

cheers

No you aint been flaming me. I just expected it with my suggestions this time as I didn't put a lot of thought into them.

But on the top buggy leaf Q, I meant for some arch so as to keep downward pressure on the axle. And in that case it may need pinning to keep it from causing probs.
An hydraulic ram of some kind would push the buggy leaf down and weight the axle nicely and give huge travel too. Instead of relying on gravity that is. It would just need to assist the top leaf in drooping as the axle passes a predetermined point. This could be arranged on a cantilever so their is no help from the ram until it gets past the fulcrum. As in rear hatch struts.
Or am I getting into the 4th dimension a bit here?
Just brainstorming really, it's brainstorm tag. Your turn.
LM.

grimbo wrote:We shall see if Steve gets his lwb back on the road. It has been about 4 years or more of serving as a tool chest/spare parts bin

I think you're the person at the greatest risk if he ever put a recall on all his parts though

I think there will be a lot of cars off the road if Steve ever ask's for all his parts back.
Peter.

droopypete wrote:I think there will be a lot of cars off the road if Steve ever ask's for all his parts back.
Peter.

Not me

Luigi Malone wrote:But on the top buggy leaf Q, I meant for some arch so as to keep downward pressure on the axle. And in that case it may need pinning to keep it from causing probs.
An hydraulic ram of some kind would push the buggy leaf down and weight the axle nicely and give huge travel too. Instead of relying on gravity that is. It would just need to assist the top leaf in drooping as the axle passes a predetermined point. This could be arranged on a cantilever so their is no help from the ram until it gets past the fulcrum. As in rear hatch struts.

Are you sure you aren't thinking of 1/4 elyptic? (like this: http://www.spidertrax.com/suspension_qte.htm)

The 3/4 elyptic setup will have the extra half leaf - which will be mounted upside down - this means it will want to push the axel away from the chassis, but will only be able to do so once the main leaves are releived of their load... i.e. the leaves will do all the work that you are suggesting a Ram / Air bag setup for... put what it will not be able to do is force travel (i.e. lift the car), but that isn't one of the aims here...

greg wrote:

Luigi Malone wrote:But on the top buggy leaf Q, I meant for some arch so as to keep downward pressure on the axle. And in that case it may need pinning to keep it from causing probs.
An hydraulic ram of some kind would push the buggy leaf down and weight the axle nicely and give huge travel too. Instead of relying on gravity that is. It would just need to assist the top leaf in drooping as the axle passes a predetermined point. This could be arranged on a cantilever so their is no help from the ram until it gets past the fulcrum. As in rear hatch struts.

Are you sure you aren't thinking of 1/4 elyptic? (like this: http://www.spidertrax.com/suspension_qte.htm)

The 3/4 elyptic setup will have the extra half leaf - which will be mounted upside down - this means it will want to push the axel away from the chassis, but will only be able to do so once the main leaves are releived of their load... i.e. the leaves will do all the work that you are suggesting a Ram / Air bag setup for... put what it will not be able to do is force travel (i.e. lift the car), but that isn't one of the aims here...

Yeah, I knows what yo means.
I am talking 3/4 elip.
But on the short trial I had on my zuk I found that the top half leaf had to be pulled down. I figured this wasn't the downward pressure you were hoping for.
So I am just trying to think of ways to add some downward pressure to the rear suspension setup.
I found that with a stiff leaf (with arch) would only droop so far then stop due to its inherent curve. The axle would not pull it down enough to make me happy. And the curve would push the axle down to its favorite position and then it would try to bounce.
A soft leaf would slap up and down causing some horrible harsh banging against the chassis or stops whichever you use.
So therefore my suggestion of rams to help the leaf downwards and control it droop to after the main leaf was used up, all in a controlled manner and keeping downward pressure through the tyres.
Ca va??
Just ignore my ramblings if you have it sorted out tho'.
LM