Prop-Crossmember clearance when lifting a 109"

[ToyRoverlander]

I'd suggest that a 109 built with larger wheels on stronger axles with optimised standard suspension to give the belly height you want would be better than the SOA. The leafs don't hang any lower than the radius arms on a coiler and give a handy ramp to drag or push it over obstacles.

I disagree. I dont think 35s fit on a 109 with parabolics and longer shackles. They fit quite easily on a soa 109. Besides that, on a soa truck you want long flat leafsprings, not just to try and keep it low but also because long flat leafsprings flex way way easier than short heavily arched ones. They dont bend laterally as easy when they're arched.

As the springs sit above the axle the underside of the axle is totally 'clean'. No springs and plates that reduce under axle clearance.

The bits of spring that sit fore and aft of the axle also sit much higher of the ground, so they (especially the front springs) can be longer. Doing it like this you end up with a vehicle with a cleaner underside and lots more articulation than a standard setup will ever be capable of.

On this pic you can sort of see how flat the rear springs are.

Free camber is about the same as a parabolic rear spring. The spring will sit higher as it is longer.

This is what a long leafspring is capable of. The shocks that are on it do not restrict this.

Other side..

This was on 33s... the 35s only just fit on full stuff with the rear axle being 2.5" pushed back

[Soren Frimodt]

My brother had a standard oneton and he ran 35"x1.5"s on it no problem, except for a slight bit of trimming, but seeing as you have defender arches you have trimmed a lot more than he did. But of course it all comes down to what each individual prefers, this discussion could go on forever, for instance I'm running 35" x 13,5"s on my 80" with almost no lift but limited uptravel, as I have lockers in both axles and don't really need articulation for the type of terrain I drive in / the way I drive in general. Here's how she looks:

And as you can see my 80" and your 109" don't get much more different! I have anti wrap on both axles and couldn't live without it for a second, and you seem to have none? Further all the overhang at both ends would leave me stranded most of the places I use my landy. However I'm not dissing your built I'm sure it exactly how you wan't it, which is why you've built it that way. Just think that these are perfect examples of how different peoples view are on things. And it seems to me that maybe o_teunico really likes the way yours are set up so maybe it is too far off my street for me to be able to give any advise?

[o_teunico]

Soren, any advise is welcome!

Any pic of your anti wrap device?

[ToyRoverlander]

Yes Soren, you're absolutely right. Basically it boils down to, to each their own. One-tons came with 900-16 so 35s should fit as well. Does yours steer well? Those tires look huge on that little 80. Yours would be fantastic in the tight stuff, mine is a bit if a handfull in those conditions...to say the least.

Indeed, no anti wrap bars on mine. Dont seem to need them. Apparantly, from what i've read, long springs are less susceptable and i've made the spring perches 10" long to help cambat spring wrap. Also the bottom leaf on the rear springs is a quite short very thick overload leaf.

Your 80 looks like so much fun!! My girfriend loves it haha !!

[Soren Frimodt]

Glad to hear that o_teunico, here's pictures of my setup:

http://forums.lr4x4.com/index.php?showtopic=55657&page=10

Very easy to setup so it doesn't bind or wear bushes and works perfectly well had the same system on my previous 88" so have been running this setup for about 5 years with only one failure being a rose joint bolt breaking, but I sort of knew this could happen because I didn't have any rubber in the system to 'cushion' the quite extensive power of the axle wrap. This of course resulted in metal fatigue in the end. But the good thing about wrap bars is you can experiment, it won't make the car unsafe nor leave you stranded if it breaks, it'll just act like a stock leafer

[Soren Frimodt]

Yes Soren, you're absolutely right. Basically it boils down to, to each their own. One-tons came with 900-16 so 35s should fit as well. Does yours steer well? Those tires look huge on that little 80. Yours would be fantastic in the tight stuff, mine is a bit if a handfull in those conditions...to say the least.

Indeed, no anti wrap bars on mine. Dont seem to need them. Apparantly, from what i've read, long springs are less susceptable and i've made the spring perches 10" long to help cambat spring wrap. Also the bottom leaf on the rear springs is a quite short very thick overload leaf.

Your 80 looks like so much fun!! My girfriend loves it haha !!

It handles like a 4wd Mini! Well I don't know maybe axle wrap isn't as pronounced on a longer well base? It definitely makes my front end 'pop' on inclines if I don't have it, and come to think of it, it wasn't nearly as much a handicap on the 88" as it is on the 80"

Well she can't have it!

[ToyRoverlander]

Interesting. I wouldnt have a clue, havent experienced spring wrap so dont know what its like. The front end on mine does unload terribly on steep inclines which i dont really like. Will have to fit a center checkstrap to reduce it.

Haha I'll try to bring it to her gently

[Jamie_grieve]

It's not so much the lack of constant velocity that is the problem with universally jointed front axles Jamie,it's their lack of strength. The 2 15/16" U joints are smaller than the 1310 3 3/16" u joints in most LandRover propshafts, but have to cope with a 4.7:1 torque multiplication of the diffs. Take a look at a Dana 44 front axle uni for example. much larger journals and caps.

I totally agree with what you say here but I think you misunderstood me. I meant the UJ's would not be a problem if he just fitted the LT230 transfer case and 5 speed. It's been done many times in series vehicles with no ill effects and without finding rare and expensive stage one front axles. I'm guessing as a realistic way to move forward with the project that engine and transmission would be first. The fact he's going to put the disco axles on I should have seen and makes it a moot point.

Front axle tramp on leafers, aside from reducing traction,can be severe enough to bust propshafts, springs, and smash the body of shock absorbers against the swivel ball flange, so don't agree that spring wrap cushions the blows. Shackle reversal with front of spring angled up, in combination with an anti wrap bar would IMO give the best front axle performance. This basically converts the spring into a short, albeit flexible radius arm, which negates the lifting effect on steep climbs that the standard rear displaced front shackles on LR's display. Toyota Landcruisers, as an example generally have lighter front springs than the equivalent LandRover, but tramp far less and generally climb better. The problem with fitting longer springs to gain more travel,is that it screws up approach angle.I've seen a few occasions where a LandRover will easily cross an innocent looking gulley that brings LandCruisers to an abrupt halt as the front of the spring dig into the ground.

I'd agree with you that axle tramp is hard on driveline components but I wouldn't consider it a huge issue unless climbing loose tracks with an open centre diff or running a lot more horsepower than Land Rover's are normally endowed with. Any land Rover showing signs of front axle tramp needs their dampers or bushes replaced. The damper sits well behind the front axle mounted to the spring bottom plate and as the axle rotates the damper is brought into play reducing the tramping. I still agree the front suspension especially is awful but chassis welding is out the question here.

I'm not at all sure I agree with the spring shackle reversal in all circumstances. I'd accept your argument when climbing a steep hill but would also suggest that the springs are unloaded anyway if it's that steep and the front wheels contribute almost nothing to the climb.

Where the shackle reversal fals flat for me is when approaching a steep obstacle like a stone or even a high grip thing like a sandstone block the vehicle with the front shackle will not climb as well as the one with the rear shackle. Try it yourself with a leaf sprung thing, drive into a wall or a square block with the shackle first and the tyre will just spin and rub on the surface but with the shackle at the rear it'll climb. It's the difference between pushing a wheelbarrow through a hole or into a kerb or pulling it over which works every time. A spring over axle conversion here would make the 'wheelbarrow effect' even worse with front shackles.

A leaf sprung Land Cruiser reverses up a steep hill as well as it climbs them. I've had a couple of BJ40's and an FJ40 and put their superior climbing down to longer springs and better engines.

My second argument against the reversed shackles is the spring is way more likely to break when the wheel hits something and is in compression when winching instead of in tension. The drag link is pushing more against the shackles which if extended or designed for maximum travel are more likely to lead to poorer steering response.

Severe braking also puts the spring on a rear shackle setup into tension and pulls things into line and is stable, front mounted shackles are unstable under heavy braking with soft springs designed for articulation. Any play or defective bush will show up as death wobble in a front shackle before a rear shackle.

To achieve lots of articulation with cambered springs will require that the axle no longer stays perpendicular to the chassis. Because the axle is firmly clamped to the springs via the U bolts,The axle cant pivot around the centre bolt. so this angular displacement of the axle must be due to laterally twisting the springs which they were not really designed to do. Starting off with flat springs on a SOA set up allows far more easier articulation with less lateral spring distortion and less rear axle steer IMO.

Starting with flat springs means that you are relying on the spring in compression to push down the wheel on the other side simply using the flat spring as a fulcrum. Equally you are relying on light or single top leaves to allow the spring on the other side to be pushed down thus ending up with a heavy wheel and a light wheel. Leaf springs obviously can't dislocate like coils. Much better IMO is to have a large free camber but low spring rate that when on level ground the spring is compressed up to about half of it's travel or more. In the same situation as the flat springs the wheels will be in the same place but the light spring is still pushing down carrying some weight and the compressed spring is stuffed more taking less weight. This will result in more equal corner weights than with flat springs. I only run 6 thin leaves in the front of mine with the PTO winch, lots of metal and the 6.2. The springs aren't completely flat but nearly. The eyes line up with the centre of the axle at ride height.

On a SOA setup I agree you have to run flat springs or raise the suspension mounting points which isn't easy on the front. On the rear, no reason not to run cambered springs and the outriggers flipped upside down and the shackle on top.

Toyroverlander, I really like your vehicle and how you've set it up. Good axle choice too without getting silly. I see you have moved your spring mount forward for a longer spring, unfortunately that's out the question here because he can't touch the chassis at all. What I said about the leaf springs still holds true whether SOA or not. Your leaf spring in the picture has remained straight and not allowed the wheel to stuff up into the arch and is limiting bump travel and might actually break if it's allowed to move too far without a bump stop. The other wheel on droop is hanging there on the first leaf lifting it up without the 2nd and 3rd leaves contributing to grip.

Interesting you have chosen to mount the sliding part of the prop at the diff end where I would have thought it gets rattled up and down more and more likely to pump water into itself. You obviously know what you're doing from the rest of the vehicle so am curious what I didn't think of there?

[bill van snorkle]

Some of the points you touch upon Jamie reflect the reality that leaf spring suspension is a whole bag of compromises for an on road/offroad vehicle, when the spring is expected to locate the axles for/aft and laterally,resist axle wrap, in addition to providing for cross articulation and a degree of ride comfort for the occupants as well as having some capacity to carry some payload.

My own experience with leaf front re climbing abrupt obstacles is actually opposite to your own. I actually find landrovers quite hopeless in those situations compared to leaf Toyotas, Jeeps etc with shackles up front.The only way I could make a stage one reasonably competent and behave itself offroad was after fitting a tramp rod similar to Sorens but centrally mounted to the axle and running forward and inline with the spring hangers, in addition to removing a couple of leaves and fitting longer military dampers. Most of my 4 wheeling friends are 40 series LandCruiser owners, and some of them have done front shackle reversals. some claim an improvement in medium speed ride quality over rough roads, but get examples of both shackle layouts on my knarly gulley tracks and it becomes very clear which is the better setup at keeping the wheels hooked up.

On a long wheelbase vehicle such as the ToyRovLander, where rear overhang is significant, longer rear springs are not going to hurt departure angle whether SUA or SOA, but it is up front where my previos comment on approach angle applies. True that with a 6" chassis lift the approach angle is not really affected, but I would personally prefer the advantage of SOA such as reduction in snag point under the axles, higher roll centre and better articulation without raising the chassis that much, and a lower LandRover with longer springs is going to have a poor approach angle.

I would like to comment on ToyRovLanders rear articulation but I must leave for work now so maybe later on.

[o_teunico]

Soren, your bar looks very easy to fabricate. I like that. Most bars I have seen, mainly built by americans, use shackles.

[ToyRoverlander]

Thanks Jamie! I think i misunderstood when you talked about flat springs i thought you ment installed on the vehicle with weight on it, while you must have ment uninstalled. Mine have a fair bit of camber but are fairly soft, hence they are nearly flat on the vehicle with weight on them. They're still capable of a fair bit of uptravel. The 35s only just clear the wheelwells and arches.

My view on this setup is the following. When mine is at ay 75% of its articulation it might start to lose traction on the drooped wheel. But as it hs that much articulation its already way beyond the point that a standard vehicle would already be lifting its wheel. Wheels in the ground equals stability. And for those moments it hasnt got enough traction due to a drooped wheel, it has lockers front and rear. I love the combination of lots of articulation, for stability and traction, and twin lockers.

My rear springs dont go past flat, or perhaps the tiniest bit of reverse arch, as it has a thick overload in its pack and it just doesnt have the weight on it to force it any further. Doesnt have bumpstops actually on the rear axle.

I didnt choose for the slider joint of the driveshaft to be at the bottom. Thats how it came from the company thst made it for me. On the other end is a big double cardan joint. I keep it well greased and like to think that whatever makes its way in there will work its way out at the bottom which is the male splined end.

Bill, when going sprung over one can run larger tires to help offset the longer front springs. I fitted the bumper in front of the lenghtened frame rails which hurts approach angle. Its annoying sometimes when it hits rocks trees or whatever. A mate of mine fitted it so that the front of the bumper sits flush with the front of the frame, saving 4" compared to mine.

I do have lots of room to stand though which is handy for servicing.

[bill van snorkle]

I was going to comment on ToyRover Landers rear articulation, but it is really a comment on any vehicle with widely spaced springs. I have mentioned on some other threads that a solid axle suspension can be likened to a see saw or balance beam with two off centre fulcrums.The further apart the fulcrums are spaced and the closer they are to the wheels, the less weight that the stuffed wheel can transfer to the drooped wheel during articulation. Once a spring on the drooped side reaches its free camber state, it is only the weight of the tyre and part of the axle assembly, plus the weight transfer from the offcentre see saw fulcrum that is providing the drooped wheel with any traction. Drooping beyond free camber, the spring changes from being a compression spring to a tension spring, and if all leaves are firmly clamped together it has the same rate in tension as in compression.So a typical clamped LR rear spring with say a spring rate of 300lbs per inch will likely only droop a further 1.5" before the tension in the spring has overcome all the weight of the drooped wheel and axle, and that doesn't even factor in the torsional resistance of the spring on the stuffed wheel side. Tricks like mounting widely spaced springs to the axle on laterally rocking saddles remove spring torsion from the equation, and if an antiwrap bar is fitted, the leaf clamps can be loosened or eliminated. Over slung springs also generally gives a higher roll centre, which tends to give less body roll and higher articulation resistance, that also could be addressed if one wants to get a bit more radical by moving the springs closer together like on SWB LR's.

[Jamie_grieve]

I was going to say something similar too but my reply was getting wordy as it was. The only thing I'd add to that (purely for further explaining what you are already saying) is that a vehicle with narrower spaced springs would give more articulation for the same amount of spring travel. You could do this to the point of being ridiculous by mounting the springs inboard of the chassis rails. I looked at this when I built mine but the diff gets in the way.

[ToyRoverlander]

All very true. Thats also one of the reasons for going to even longer rear springs. As the front springs are closer together they are capable of more articulation than the equal lenght springs that are spaced further apart.

I tried to achieve a front rear balanced suspension. The rear now still has more. I moved the rear springs a bit further inboard as well. Basically as it was easier to create new springmounts that way.

I wouldnt completely eliminate the leaf clamps. I find my bottom leaf getting out of line with the other 3leafs after driving through some flexy stuff. They do keep the leaves aligned. Mine are very very loose.

[bill van snorkle]

I was going to say something similar too but my reply was getting wordy as it was. The only thing I'd add to that (purely for further explaining what you are already saying) is that a vehicle with narrower spaced springs would give more articulation for the same amount of spring travel. You could do this to the point of being ridiculous by mounting the springs inboard of the chassis rails. I looked at this when I built mine but the diff gets in the way.

Or one could go even further and take a leaf out of Scammells book and go the a centrally pivoted transverse leaf spring suspension located by a One Link Wishbone. A lapsed member from here, 'Night Train' built a 6x6 Landrover with a Scammell Constuctor type front end.

[Snagger]

Or one could go even further and take a leaf out of Scammells book and go the a centrally pivoted transverse leaf spring suspension located by a One Link Wishbone. A lapsed member from here, 'Night Train' built a 6x6 Landrover with a Scammell Constuctor type front end.

Like a Triumph Spitfire?

[bill van snorkle]

Like a Triumph Spitfire?

It's been a while since I have seen one, but I think the spitfire's transverse spring was centrally clamped as opposed to pivoted.

[Snagger]

You might be right.