Newbie: Disco 6x6 from Spain

[o_teunico]

Does anyone know how much shorter is a "Wolf" short nose diff when compared with a Rover one?

And length of a ZF 4HP22/24 and Chrysler Torque Flight A727?

Will such a manual-auto combo work OK when reverse is selected in the manual one?

I have thought that a ZF auto will be easier to obtain ant it´s overdrive 4th could favour the use of super tiny 205/50R16 road tyres for city use, avoiding RRC roof conversion.

[bill van snorkle]

I'll try to answer some of your questions in no special order.

Cheap underdrive? I made my own underdrive by adapting the front half of a scrap Fairey overdrive to a 2 speed t/case planetary reduction unit(Borg Warner 1339) from an old auto Jeep CJ7. A mate has a couple of scrap GKN overdrives to suit LT230 that he was going to give me to see if I could design a similar adaption for him, but he hasn't dug them out from his shed yet.

I believe that the Wolf P38 type short nose diffs aren't as good as the long nose ones, due to the closer spaced pinion bearings.

Michele made the thread titled 'Bills LR's' in the Members Vehicles forum, page 5 or 6 I think.

From the side on photo, if we knew the diameter of the tyres, the wheelbase of the Volvo could be calculated near enough.I'm guessing it's around 72 inches front to centre.

I think the long integrally cast bell housing of the Puma 6 spd box makes adapting to TDI very spendy.

I would have imagined freight cost to get cheap Series t/cases to Spain wouldn't have been too high? Maybe Forum Courier Service?

Your overall height restriction due to the bridge, rules out having enough clearance between chassis and axles to allow for good bogie articulation, unless you make the height adjustable by doing as I did on my 6x6 and mount the leaf spring pivots on a crossbeam fixed to the chassis via telescopic struts. Air suspension on front axle?

Could you make sliding windows for the Disco doors ala Series LR's.Can't see how Lambo style doors can work when vehicle is moving.

Based on measurements taken from my RangeRover, when the axle is up against the bumpstops, the top of the axle tube is higher than the transfercase output shaft. So on your latest sketch the rear propshaft will likely clash with the leading axle when the bogie is articulating, unless you run a 2 piece propshaft and support bearing mounted on the leading axle.With a rear axle spacing of 100cm (40'') and the length of the diff nose of 34cm, measured from axle centre to universal joint centre, that should give you an effective rear propshaft length of approx 65cm, good for around just 30cm of bogie articulation.

Cannot help with ZF dimensions, or if you could easily make it work without hydraulic pressure to activate the ratio selecting clutches.

The hinged chassis idea I mentioned in an earlier post has been knawing away at my brain. It would give the vehicle modification authorities heart failure, but if it worked it could be a way of getting exceptional bogie articulation without the need to raise the height of the chassis. Not applicable to a station wagon body of course, but for a pickup or trayback with a separate rear body it could work.

We used to be able to register these type of vehicles as tractors, but i think that loophole was abused by builders of Tuff Truck Challenge vehicles, so that option has been closed off to us unless the vehicle is based on an original tractor.

I don't have any level flat surfaces on my land with which to accurately measure my RangeRover, but It appears to be 1.8metres high on 29'' tyres 35s would raise it a further 75mm.Raising suspension 125mm will reach your 2 metre limit. looking underneath, it appears that the bottom of the chassis is about the same height as the bottom of the axle housings. So to bolt a diff assembly directly to the bottom of the chassis would have the belly wheels around 40mm lower than the road wheels. Raising the chassis 125mm would give a groundclearance under the unsprung belly wheels of only 85mm, so you would get a rough ride offroad and the chassis would be subjected to some severe torture.

[dirtydiesel]

I found this article some time ago. Some interesting pics.

[bill van snorkle]

That brought a tear to my eye reading that again after all these years Dan. Thanks.

[Night Train]

Given Bill's input I should chime in too.

My 6x6 used a front and rear suspension in the style of a [url=]http://hmvf.co.uk/forumvb/showthread.php?7308-Scammell-Constructor-Gallery/page14Scammell Constructor.[/url]

The front axle had a transverse leaf spring free pivoting on a bearing, and the rear had inverted leaf springs also free pivoting.

Not an easy one to produce but effective for load and torque balance. I also used wider axles, series 3 Salisburys with long shafts in both sides.

I also designed and built my own remote mounted, 2 rear, 1 front output transfer box with PTO. It gave three speeds, a high overdrive, 1:1, and a very low underdrive.

The only snag was that it was a four shaft box so the axles and diffs were inverted and driving backwards.

I must admit that were I to build another 6x6 I would look at independent suspension with the diffs mounted to a backbone chassis.

I would still use a load sharing suspension on the rear bogie, either inverted leaf springs ball jointed to the ends of the wishbones, or coil springs and cranks likewise, as in your post 49.

The Scammell walking beam is a good but heavy system. Scammell determined that the gears within the beam had to be a 2:1 reduction to the wheels to prevent the beam unloading the leading wheel. However, under braking the leading wheel would dig in and the trailing one would try to lift.

A good balanced system would counterbalance both driving and braking torque reaction, as in the Scammell Constructor bogie, and also balance teh loads on both leading and trailing axles/wheels.

[bill van snorkle]

I was wondering when you would spot this thread Night Train. I read about someone that fits both your and your LandRovers description on the Guns and Rovers forum from memory.The post was written by an ex policeman.I had to smile as it brought back memories of me trying to convince the plod that my 6x6 wasn't home built, but a genuine LandRover factory prototype that was originally supplied to the Australian Army for evaluation testing.

BTW, how did the council let you get away with pulling your truck to pieces in what likes like a main road in a shopping precinct?

Anyway before i forget. I just measured up my 107'' chassis to get an idea of the overall length it would be in inches.So with both rear axles reversed, and with a wheelbase of 74"+40" and 36" tyres, it would be 150" long.With my 2 1/4 litre engine at 26" long from fan to back of block and tansmission length of 32" from front of flywheel housing to back of handbrake drum, there is just enough space to fit it all in including a winch up front and have no overhang beyond the tyres and retain the full articulation of my old truck.

Longer engine transmission assemblies would obviously require a longer chassis or shorter primary propshaft and reduced articulation.

[FridgeFreezer]

The tyres on the shorty Volvo 6x6 are about 40" TSL boggers from memory, standard issue are 9.00x16.

You can find complete Volvo trucks in running order for ~£5k (very rough estimate), could save a lot of time and money and be road-legal...

[Nigelw]

I found this whilst surfing the tube and wondered if tuenico would find a few other possibilities from its offerings in terms of engineering?

I kind of wonder if it is feasible to mount a prop to the front of the first diff and have the two axles driven from it, sorry, rambling, just watch and see how the drive train works and get your own ideas together from it....

http://www.youtube.com/watch?NR=1&v=g8rW9IybwnE&feature=endscreen

I have taken this thread as a thinking platform for future projects and maybe something from it will be seen in a future build??????....

[Night Train]

I was wondering when you would spot this thread Night Train. I read about someone that fits both your and your LandRovers description on the Guns and Rovers forum from memory.The post was written by an ex policeman.I had to smile as it brought back memories of me trying to convince the plod that my 6x6 wasn't home built, but a genuine LandRover factory prototype that was originally supplied to the Australian Army for evaluation testing.

BTW, how did the council let you get away with pulling your truck to pieces in what likes like a main road in a shopping precinct?

I don't get on here much nowadays. My projects tend to be pedal powered or electric now but also long term illness is slowing me down and limiting my project progress. Also had an urgent bit of building work to do on the house through December and January, on top of current renovations I have to finish before I get married.

When I was building my truck I got all my insuarance, road fund licence and MOt test all at the same time so it was road legal. Then I started work. So long as it was 'road legal' the Police and council didn't trouble me. All the work was planned to get it road worthy and legal again at each anniversary for it allto start again, stage by stage.

Not sure if one could get away with it now though, I doubt the IVA would be cost effective if it had to be done two or three times over as the project progressed.

[Night Train]

I found this whilst surfing the tube and wondered if tuenico would find a few other possibilities from its offerings in terms of engineering?

I kind of wonder if it is feasible to mount a prop to the front of the first diff and have the two axles driven from it, sorry, rambling, just watch and see how the drive train works and get your own ideas together from it....

http://www.youtube.com/watch?NR=1&v=g8rW9IybwnE&feature=endscreen

I have taken this thread as a thinking platform for future projects and maybe something from it will be seen in a future build??????....

That would be sort of how I would do it now.

A space frame back bone supporting diffs and double wishbones. A single propshaft line running above and to one side of the diffs with a dog clutched drop box to each diff pinion. Any or all diffs can be clutched in/out as required. It does mean running with only a single drive axle on tarmac but that is less of an issue for the sorts of thing I would do with it.

[bill van snorkle]

I found this whilst surfing the tube and wondered if tuenico would find a few other possibilities from its offerings in terms of engineering?

I kind of wonder if it is feasible to mount a prop to the front of the first diff and have the two axles driven from it, sorry, rambling, just watch and see how the drive train works and get your own ideas together from it....

http://www.youtube.com/watch?NR=1&v=g8rW9IybwnE&feature=endscreen

I have taken this thread as a thinking platform for future projects and maybe something from it will be seen in a future build??????....

That is basically the Pinzgauer layout but minus the portal hubs. Very complicated and difficult to reproduce the way Steyr made it with 2 crownwheels and 2 pinions in each diff to\ transfer the drive to the next and to provide articulation of the independant half axles. Worm drive differentials as used on the Kruppe Protz would be simpler, but the last vehicle i am aware of that used worm drive diffs was the Peugot 404.

If you follow Nightrains Scammell link Teunico, you will learn that even with all the factorys resources, Scammell engineers got it seriously wrong with propshaft angles and bad vibration on both the Constructor and Explorer vehicles, so be carefull with your final layout before commiting.

The Tatra/Pinzgauer layout with short swinging half axles gives poor articulation, and whist they work ok in the Tatras 8x8 configuration, I've been a bit underwhelmed by the cross country performance and relative lack of stability of Pinzgauers.

[Night Train]

Here's another way of achiving what I was describing.

[http://www.shinjeong.co.kr/e/product.html?p=isas⊂=isas/url]

It keeps the wheels vertical instead of the swing arms tucking under during full drop.

Drop boxes to the diffs would save having a drive through diff made up.

[bill van snorkle]

Here's another way of achiving what I was describing.

[http://www.shinjeong.co.kr/e/product.html?p=isas⊂=isas/url]

It keeps the wheels vertical instead of the swing arms tucking under during full drop.

Drop boxes to the diffs would save having a drive through diff made up.

The double wishbones are definately more stable than swing axles but the all important axle articulation is still limited, particularly on steering axles where a single cv joint at the wheel end needs to articulate in 2 planes simultaneously.

[FridgeFreezer]

Ooooh don't mention Tatra 813's, they are awesome. I know Bill doesn't rate them for off-roading but there's not much else out there capable of towing 100t and completing the Dakar. 18-litre aircooled V12 diesel, mmm...

[o_teunico]

Bill´s LR http://forums.lr4x4.com/index.php?showtopic=6428

I have been consulting both spanish and european regulations, and I could make ANY moddiffication to a vehicle and register it as PROTOTYPE. Unfortunately I will need to be a "BUILDER" (how is that achieved?) and the car will be road legal for a short period of time, just for testing before "production" starts.

In my area there are quite a lot of blacksmiths that are approved saloon car and farm tractor trailer builders. I have contacted the one that 15 years ago made my fathers trailer out of a Fiat Panda scrapyard axle. For little money he will give a VIN and Logbook to a homemade trailer, as soon as it is sized as one of his "production" models.

So, I could make a trailer with collapsable hitch and LR axle that will move up-down, but no left right, and also cappable of tilting. When used with the Disco it will a kind of GammaGoat/MB Hexawheel. Traction will be delivered via a farm tractor max 3000rpm propsahft from rear axle with freewheeling hubs on axle.

Belly axle will be driven with belts/pulleys from LT230´s brake drum.

RRC low roof conversion and rear end will give height clearance and enchance better trailer/LR articulation.

Chopped Disco + mini trailer will have a length of about 480cm, beeing able to use multi lot parkings with a deployable camping shelter on it.

A mini version of this will be used with the trailer on hollidays.

[o_teunico]

As Bill said, belly axle should be located above chassis. This could lead to the necessity of lowering engine+gbox (=better propshaft angles but less clearance with obstacles) and a body lift for clearance between body and new axle.

It´s not a Disco chassis, it´s a 70s Rangie, but you get the idea

[o_teunico]

About Lambo Doors, I could see between door and A pillar

Of course at very low speeds.

I don´t consider practical making bespoke sliding glass for it. A broken glass will have no other solution than making another bespoke one. Forget about off-the -shelf parts.

Series ones will be illeagal as they don´t have post ´82 "E" marking.

[bill van snorkle]

Ooooh don't mention Tatra 813's, they are awesome. I know Bill doesn't rate them for off-roading but there's not much else out there capable of towing 100t and completing the Dakar. 18-litre aircooled V12 diesel, mmm...

It's not so much that I don't rate them for offroading. They obviously do very well in heavy vehicle trials.It is just that they lift wheels so easily in relatively mild terrain that I believe something with solid axles, say based on a MAN 8x8 should be more competent.

There is a Tatra 813 not far from where I live that has been lying dormant for over 10 years. The owners original intention was to use it as a recovery vehicle for broken down or otherwise immobilised LandRovers,Cruisers etc in the mountains, but he found it was far to wide to navigate our forest trails , and also had a disconcerting habit of the swing axles causing the truck to crab down downhill on sideslopes.I have noticed a similar thing when following a 6x6 Pinzgauer in similar terrain.

[Nigelw]

Here's another way of achiving what I was describing.

[http://www.shinjeong.co.kr/e/product.html?p=isas⊂=isas/url]

It keeps the wheels vertical instead of the swing arms tucking under during full drop.

Drop boxes to the diffs would save having a drive through diff made up.

this is by far the best way with fully independent suspension!!

In my opinion(worth the space on this screen) make the Disco a nice car to use as a daily driver and make something properly, the idea of using the free Disco is romantic at best, but silly as it needs so much modding to make anything work, you have already admitted cost and regulation will hamper the conversion!!!

There are ways to do it but in your part of the EU it is the same as mine, you could not actually change the roof of the Disco to lower the roof line to the height of a RRC as it is far above the COC that your vehicle must have, and as far as fabrication goes anything is possible but not to drive on Spanish roads and not with the mods you are proposing, sorry to be a downer but I can't see the Disco being anymore than a Disco in Spain, make the step and custom build something special and try to get it prototype registered and go from there, blank canvas is the only way forward for free thinking, the Disco already has limitations that are too difficult to overcome and be within anysort of budget, I would look closely at the independent and then build a rig for it to be built into, you can always look to salvage the engine box from the Disco to save cash but look objectively at the project, to stay within your parameters the Disco is the wrong choice!!

[FridgeFreezer]

Interesting design... I've now completely forgotten what the original reason for all this was? Looking at the picture, I am struggling to identify the problem it's solving compared to a normal 4x4 truck.

[Nigelw]

Interesting design... I've now completely forgotten what the original reason for all this was? Looking at the picture, I am struggling to identify the problem it's solving compared to a normal 4x4 truck.

That's what was my first impression of the design, but my immediate thought was tidy the Disco up and sell it then save for a 90, I have been thinking about the many ideas and the thoughts from far more experienced builders and yes a million things can be done but I struggle to see any benefits from trying to stay within the build of a Disco? Save for a bigger vehicle than a far more agile 90 there may be some leverage in the lower ground pressure for the carrying of supplies for an overlanding trip maybe?

I wonder still for the swinging bogies from the Boomerang? On a 90 that would be something to behold and then if it were a truck cab it could be fitted with a hi-cap tub to extend over the rearmost wheels and you would have a much bigger load bed, Now there is an idea, start 10" smaller than a Disco wheelbase and end up with a vehicle the same size by the end of it......

[o_teunico]

After eight pages of discussion and great feedback from the LR4x4 community I have (nearly) abandoned the idea of making a 6x6.

Legality, budget and bulding skills I don´t have, along with the fact that 6x6 is not neccesary better than 4x4, had showed me that a good 4x4 will fullfill nearly all my needs: a capable offroader suitable for daily driving arround city.

Standard tyre size belly axle has appealed me a lot. It will be cheap and simple and will give the vehicle nearly same trench-crossing ability of a propper 6x6.

Powered pitch-roll trailer will also be relatively easy to build/register (under 750kg GVW trailers don´t need MoT test, insurance or number plate) and will be usefull for hollidays and firewood collecting arround farmhouse. Let´s face it, at best, trailer will be used 4 or 5 weeks per year.

Only thing that I will have not solved will be the excessive turning radius the car has. I should have a look at those post about steering geometry and Akermann angles, as this could help.

Dieseldog, what´s the meaning of "COC"?

I have been thinking that if I maintain 205R16 for city use I could save the roof conversion. Even a 2.1m tall the car will pass under the bridge at it´s tallest point.

[o_teunico]

I have just located my copy of the book "Land Rover Series II 1958-1971" by Brooklands Books ISBN 0 948207 98 1.

This book was extremly important for me. It was 1997, I was a 17 years old teen with Land Rover madness and mine was the only case in the area.

Land Rover´s 50th anniversary was nearly there and I went to a classic and oldtimer car gathering. There I found lots of memorabilia of LR, and there it was, a book that showed me that Land Rover madness was spreaded all over the world and that I was not alone.

In this book there was also an ad from Land Rover Owner International magazine. Of course I sent the subscription application. That greatly improved my english level, and one year later I obtained my First Certificate in English from Cambridge University.

I took the book to a print shop and they made for me a series of posters in A3 size of Bill´s 6x6 climbing over a fallen tree for decorating my bedroom.

Here just some pics to complete those posted by Dirtydiesel

[Nigelw]

COC = Certificate Of Conformity, basically for you like me a modified vehicles need to retain characteristics from the original COC to meet an amendment of the registration otherwise any radical alterations would need a complete safety assessment of the build and knowing what Spain is like from my mate Ians documents for his Land Cruiser with a bicycle rack suspension upgrade and wheels & tyre swap made it expensive to say the very least and they were trivial things!!!!

[o_teunico]

Thank Dieseldog!

Just an idea for a prototype...

Independent suspension has many advantages, but wheel travel is certailny not one of them. How could this be improved?

Think about this design...

...attached to a twisting chassis, as used in compact articulated farm tractors...

The chassis will provide the travel that the suspension itself is not capable of delivering.

Chassis could be lockable for road use.

Chassis' will need to rotate concentric to propshafts, like the TATRA design.

For even greater articulation the chassis could also be capable of up-down movement, as seen in MB Hexawheel design proposal.

Here an articulated prototype from 1955 (Dodge WM300)