Modifying 110 suspension

[Luke]

Some info to warm up the discussion.

Every vehicle has a carefully calculated castor angle. This is the angle of the steering pivot relative to the ground. On wishbone and leaf suspensions this angle stays relatively unchanged with suspension height. On primitive (sorry I couldn't resist) swingarm setups the higher the lift the closer the castor is to zero. At low speeds you won't notice the difference, but above about 20kmh the vehicle will wander even more than it originally did (anyone who's driven a series will know about wander, it's not only about play in the linkages); and the steeering will have less of that comforting return to centre feeling. Modified swingarms, excentric polybushes and offset chassis mounts exist to bring back the specified castor angle. Without it at worst the vehicle is more prone to rolling over, and long trips become even more tiring.

Anti roll bars: one of the principles of LR design is to keep all four wheels in contact, to keep the load carried by each wheel and its patch of ground as low as possible. The moment you wave a wheel, the other three take the extra weight. The good news is that in sand, which is always in movement under the tyres that doesn't matter, and with a bit of power you can often get away with having a wheel in the air.

LR have worked hard on their road dynamics; although there is body roll, some of this suppleness is there to keep load distribution as even as possible in curves. Slapping an anti roll bar underneath will certainly hold the body straight, bringing you closer to family saloon handling. BUT it will also ensure a greater mass transfer to the outside wheels, on high profile tyres (7.50 x 16) this causes squirm and scrub and excessive wear on the outside edge. by the same measure it also reduces your effective axle width on the side that counts, bringing the vehicle closer to falling over.

The running gear of a LR (and a Toy for that matter) resembles that of an underdimensioned lorry, if you only expect lorry handling you will be pleasantly surprised. Even after all the mods that exist, it will still be a live axle vehicle with all the handling disadvantages (and off road advantages) that come along with it.

Ultimately we learn to be happy with what we've just spent lots of money on.
Happy trails
Luke

[Diff]

Andrew, the Standard hard top springs, and the rest of the world spec rear springs are the same, and the part numbers are in my previous post, though since approx the mid 1990's, Landrovers do not have left and right rear springs on the 110, but use NRC 6904 (red+green stripe) - 330 lbs/inch, on both sides. I don't have the part no.s for the 130 springs and helpers to hand, but from what you describe, these will be too stiff for your application. 110 rear springs will NOT fit on the front of a 110 without modifications to the spring seats. The hard top rear springs would be totally unsuitable anyway due to their 330 lbs/inch rating. The 110 rear springs(180lbs/inch) as fitted to UK county station wagon models with the self levelling unit may be suitable as heavy duty fronts, but as I stated, won't fit without modification due to the larger diameter.
The problems of ramp breakover you have described, are an attribute of the 110s design. At 110 inch wheelbase it probably had the longest wheelbase of the vehicles whithin your group + the deepest chassis, hence the problem you describe. Since you are not overloaded, the standard springs should be fine, and you will have to live with the limitations of the vehicle design unless you spend a great deal of money as (illustrated above) on a custom suspension system which may or may not cause other unforseen problems. A non standard suspension lift as previously described is the route some people take and it may work well for them, but at a price.
Hope this helps.

[Andyk]

Hi,

I have fitted 130 coils front and rear, without the helper springs, to a 110 station wagon without the levelling system.

A bit of lift and a bit more sway, but generally OK.

Cheers,

Andy

[This message has been edited by Andyk (edited 25 November 2002).]

[ctc]

A small apology to make, after further research, it turns out the front springs on my 110 are the front springs off a Rapier not the standard rear 110 springs.

[SandyM]

Very interesting thread.

AB, I am very interested in your suggestion of the air springs.

I have been doing some reading about these - it seems they are used quite a bit on motor-homes to reduce body roll. It seems that they will cost around £200 for each rear axle, and require no modifications (purely an add-on).

It gets better - on my 6x6, I could also interconnect the pair of left-hand rears, and (independently) the pair of right hand rears. This would give the rear axles some very desirable bogey attributes, while still stiffening the suspension against side-to-side motion.

As I have on-board air already, it should also be pretty straightforward to have independent control, from the cab, of the pressure of the left- and right-hand pairs, which would enable me to compensate for uneven load etc.

Anyone have any experience of these air springs? Are they durable and reliable? Any nasty side-effects? Also, the bogey idea just occurred to me, so I may not have thought it through fully. I was musing over the effect that interconnecting left and right would have (I believe it would make the body roll FAR worse!), and then got to thinking about a front/rear interconnect... So any comments on this would be welcomed.

Luke, I take your point about regarding our vehicles as if they were lorries - you are absolutely right. None of us can expect car-like handling from a proper expediton vehicle. But there are things we can do to reduce excessive body roll. The challenge, as you point out, is to do so without simply transforming the problem into something else, possibly more dangerous or damaging.

(Incidentally AB, just to clarify, anti-roll bars were an option on Defenders, so it's not a case of my taking them off, it's a case of whether I fit them at all. I would try these as my first option, except that I can't see any way of attaching them to axle #2, and I think they will be ineffective / harmful if only fitted to axle#3. Still an option to consider, though).

Regards to all,

Michael

[Ian Bradshaw]

I just got back from RIM in my overloaded '94 110 CSW. I was running 'Terrain Tamer' shocks made by Gabriel and standard front springs / heavy duty LR rear springs as mentioned earlier in this thread(3050kg if I remember correctly) without helper springs. (Plus the Boge self levelling unit & ARB still in place)

Unfortunately, we were doing mods and packing up until 2am the day we left (at 2am!) and didn't get time to test.

I agree that payload should be minimised where possible, but I still had between 1000 and 1200kg to carry, including 200kg 500mm behind the rear crossmember (my XR650R). Weight is the most important factor for suspension set up, if the dealer is not interested in what payload you have, or says it makes no difference, it may be best to look elsewhere.

The gas shocks had transformed the ride, I thought they were excellent, until the rears broke (the first between Choum & Nouadhibou, the 2nd in the Atlas). It wasn't much fun driving back to the UK with a single front shock mated up to the rear!

I took the broken shocks back to the Importers (Paddock), who refused to replace them saying that they were not suitable for severe off road use and the next pair would be destroyed again. They did give me a refund & said they would not be selling these shocks to people undertaking similar adventures. Our driving was generally fast & somedays we were airborne 4-5 times with 8-10 hits on the bump stops.

I bought a pair of OE shocks from DLS, but the ride is lousy again! DLS had Delphi and Bilstein gas shocks available and would have made more money from them, but were honest enough to say they had plenty of customers that had broken them too.

I am quite happy to accept that giving the rear shocks twice as much work to do (in terms of weight) plus the enhanced damping of more effective gas units is going to result in a lot more heat to dissipate. Do this over a long piste, with relatively high temperatures & they are likely to break. (Both of mine bent their damping rods, due to the heat, then snapped) Carrying a couple of spare rears is probably wise. I shall run a dual-shock set up on both sides at the back next time.

BTW the front springs were adequate and the back was slightly undersprung. Part of the way we travelled with an OME equipped 110CSW, their rear end was bouncing more than ours.. I am not sure who supplied it but they got the wrong spring and damper rates. At least nothing broke though :-)

IanB

[mac]

as someone else has stated,the best option for your 110 would be Old man emu.The wolf option is not designed for the use that you intend,far too stiff.

[A.B.]

SandyM,

The air bag suspensions, especially Firestone, are very strong and reliable providing they are properly installed. If you’re going to install the inside the coil spring air bag, make sure you get the correct one for the springs you have not just for the vehicle. If you’ve changed to a heavier duty or more travel version then mention that to the air bag manufacturer. If you’re going to install a regular air bag along side the spring make sure it has the correct travel, otherwise it might just rip if it’s too short. Some air bags have an internal bump stop so make sure it doesn’t bottom out before the vehicles bump stop. Also make sure there’s an inch of clearance all around the air bag. The bags can usually withstand flying rocks and pebbles but I would install some sort of rubber shield around it for extra protection.

These bags have been used extensively off road with great success. I’ve seen them in hill climbing buggies, in a Paris Dakar truck and in a Baja 500 pro truck. They are optional in a few upscale 4x4 like the Expedition the H2 (Hummer) and the new Range Rover.

If you feel adventures you might to install them (a heavy duty version) to replace the springs entirely. This is the ultimate setup as you can easily inflate or deflate it to handle whatever load you carry and you’ll have the most comfortable ride ever J.

You can use the air bags to improve articulation. Connect the left and right air bags via a manual or electric valve or solenoid. When the valve is closed the Air bags will provide the best stability and load balancing. When going slowly on rough terrains, open the valve so the air flows freely between the 2 opposing air bags. When a tire is lifted on a rock or whatever, the air bag will compress and the air will escape into the other end. This will force the stiff suspension to travel more downwards and provide more articulation and traction. Also the vehicle will sit a bit more level while crawling on the rocks. But this should only be practiced at slow speeds.

If you install air bags at the 4 corners of the vehicle then connect the right front to the left rear and the left front to the right rear. This will improve slow speed articulation and travel at all corners of the vehicles. Again: only at slow speed.

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A.B.

OasisPhoto.com – Images from the Magical Sahara.
ShortWheelbase.com – Jeep preparations.

[A.B.]

<font face="" size="2">..including 200kg 500mm behind the rear crossmember (my XR650R).</font>

Ian, I’m curious, how did you mount that XR on the back of the vehicle? Any pictures?

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A.B.

OasisPhoto.com – Images from the Magical Sahara.
ShortWheelbase.com – Jeep preparations.

[Andrew Baker]

Tnx for all contributions - I am investigating Old Man Emu and airbags with the standard set up.


Best wishes to all
Andrew

[david lambeth]

Hi
You wouldnt happen to be the Andrew Baker that lived in Chiddingstone???

[Andrew Baker]

Hi David,

Not far out, I used to live in Tunbridge Wells - now in Crowborough, East Sussex.

Cheers,

Andrew.