My 8x8 idea

[Chicken Drumstick]

Following up on my PTO thread. This is the idea I've been mulling over. Please note this isn't the final solution, just the idea in motion.

Take one 127 or 130 Land Rover.

Remove the body. And add two extra axles. What I'd thought of was using a front axle complete with radius arms at the rear and a 2nd steering box. This way you could have a rear steer axle too.

I thought of keep the rear most axle in the stock location to preserve the 127" wheelbase.

Then fit the other axles at equal distances between.

Lots of details to work through still.

But I'd hope to have something that maybe looked a little like this:

Any of you guys SVA/IVA experts?

I guess it looks radical, but essentially it's not all that different from the original vehicle(assuming it works), i.e.

-it would still be a 127" wheelbase double cab pickup

-the steering linkages would remain

-The gearbox would remain

-the axles would remain

-even the chassis would remain, with only additions rather than being hacked up

Anyhow, I know it's a wild idea, just thought I share my ramblings.

[landroversforever]

I think its a great idea, and something I would love to see work .

I would have thought that it would need SVA/IVA because there are still alterations to the chassis and axle configuration. But I dont know for sure.

Can't wait to see something come out of this

[need4speed]

even the chassis would remain, with only additions rather than being hacked up

Never one to rain on anyones parade but........ i think it would need to be pretty majorly hacked up. For one thing where is the engine / box going to go if the cab/front seats are right at the front?

[Henry Webster]

So not dissimilar to the Esarco, then.

http://www.lr-mad.co.uk/en/other-fc-types/8x8-forward-controls

I think you would have to start again with the chassis to make it work.

H

[Chicken Drumstick]

Never one to rain on anyones parade but........ i think it would need to be pretty majorly hacked up. For one thing where is the engine / box going to go if the cab/front seats are right at the front?

Engine and gearbox would remain in stock locations. It'd be a forward control a bit like a 101. So you'd sort of sit on top and slightly in front of the engine. Suspect my cut & paste pic would need the cab moving forward a tad to reflect this better.

Here's the inspiration behind the idea. This is a H.U.G.O. which is a development of an Esarco. As you can see it's got rather a lot of Landy bits on it.

The engine would be under an access panel. It would mean turning the cab into a 4 seater losing the middle seat. But I'd be fine with that.

I'd like to try and keep it looking a little more Land Rover at the front though, more Series IIb FC. And use Defender radiator panel, grill and lights.

The drivetrain would look something like this:

Engine and gearbox and first transfer case in stock locations. Keep the front axle all stock. And the rear most axle in the same place, although I'd run radius arms at the rear and a steering box on what would have been an old front axle.

Move the existing axle to position 3 and axle 2 would be what would have been the rear axle from your second donor vehicle. From the PTO on the first transfer box power a 2nd transfer box, which in turn powers axles 2 and 4.

I was thinking you'd simply weld some upper spring perches in place for axles 2 and 3 and then run a turret mounted shock to keep it simple and easy. Maybe something like a Pro Comp +2" shock and then some 110 +1" lift spings all round and dislocation cones on each of the 8 turrets.

You could also hook up the brakes on all the axles, although I wonder if a bigger servo might be needed.

I know it seems like a little OTT, but I just can't help thinking... "it's all Land Rover bits, just bolt them in together in a slightly different order to normal".

Should it work you'd have a vehicle not much longer than a 110, with a tight turning circle. Great visibility, good load and towing ability and I suspect something that would be more gentle on the weak Rover alxes and diffs.

8x8 traction means it should go well of road and possibly even articulate quite well with extended shocks and suitable springs.

[Retroanaconda]

There's no doubt it would need an IVA, but that's no reason not to build it.

Go for it, looks awesome

[Chicken Drumstick]

So not dissimilar to the Esarco, then.

http://www.lr-mad.co.uk/en/other-fc-types/8x8-forward-controls

I think you would have to start again with the chassis to make it work.

H

That is the main inspiration.

Not sure if any of you guys will remember this or not. But back in the 80's there was a TV program called Driving Force. Sterling Moss and Murry Walker presented on various years.

In I think 1988 or 89 their were at St Helier on Jersey and had an 8x8 and a 6x6 Esarco. I've wanted one ever since, but never seen one for sale.

Doing some more active research into them I got to wondering if it would be possible to build one instead as they used a lot of Land Rover bits.

But maybe you are right about the chassis. Will have to do a bit more investigating.

[simonr]

I think it would be a lot simpler to build a new chassis from scratch than modify an existing one. The standard chassis rises up at either end to provide clearance for the axles. If you didn't have that in the middle, you would probably have to lift the vehicle about 6" to get the same up-travel in the middle as at the front and back.

Either way, it would probably benefit from an IVA - it's not as difficult as some posts on the Internet make out.

Drive to the middle axles is the biggest challenge (you did say 8x8 not 8x4). I wonder if you could drive the middle wheels with hydraulic motors with a sprague clutch on each so the main driven wheels can turn faster than the hydraulic ones and they would just freewheel. When you are moving slowly or in reverse, the hydraulic motors come into action. This would also mean you could dispense with the axle tubes & diffs, which in turn means the chassis doesn't have to rise up as much.

It would be an interesting project!

Si

[Chicken Drumstick]

I think it would be a lot simpler to build a new chassis from scratch than modify an existing one. The standard chassis rises up at either end to provide clearance for the axles. If you didn't have that in the middle, you would probably have to lift the vehicle about 6" to get the same up-travel in the middle as at the front and back.

Either way, it would probably benefit from an IVA - it's not as difficult as some posts on the Internet make out.

Drive to the middle axles is the biggest challenge (you did say 8x8 not 8x4). I wonder if you could drive the middle wheels with hydraulic motors with a sprague clutch on each so the main driven wheels can turn faster than the hydraulic ones and they would just freewheel. When you are moving slowly or in reverse, the hydraulic motors come into action. This would also mean you could dispense with the axle tubes & diffs, which in turn means the chassis doesn't have to rise up as much.

It would be an interesting project!

Si

Cheer Simon, some very valid points and a your right about the chassis shape, I hadn't thought of that. Guess that makes a mocker of my mocks:

Not sure if this is more hard work than not. But if I used a Tdi Discovery as a 2nd donor vehicle, I wonder if I cut the chassis sections out of the Disco where the axles/springs locate and then cut the 127 chassis and insert these. That way you'd only have to box and plate the joins (same as making an 88 or 80" coiler) rather than having to construct an entire chassis from scratch?

[HPLP]

that drivetrain picture of the HUGO is amazing!

H

[mickeyw]

Cheer Simon, some very valid points and a your right about the chassis shape, I hadn't thought of that. Guess that makes a mocker of my mocks:

Not sure if this is more hard work than not. But if I used a Tdi Discovery as a 2nd donor vehicle, I wonder if I cut the chassis sections out of the Disco where the axles/springs locate and then cut the 127 chassis and insert these. That way you'd only have to box and plate the joins (same as making an 88 or 80" coiler) rather than having to construct an entire chassis from scratch?

Love your ideas. It's great to get the mind rattling around on this kind of thing.

One small problem you'll find with your thoughts re joining Disco and 130 chassis is that the main rails are quite a bit different in depth.

Don't let this stop your imagination though

[landroversforever]

I think if I was to build something like this (and I'd love too) I'd go with building the chassis from scratch. If you think about what little of the chassis is going to be kept and used, I can't imagine a lot will be kept?

[Gremlin]

If some recalls the series 'full metal challenge' a group of uk guys made an 8x8 (called octopush) based on 2 range rovers, The difference from the esarco is that they ran 2 engines and 2 gearboxes, 2 of the diffs needed to be flipped over for the whole thing to work. This will probably apply to your plans as well as you need to offset the diffs to the other side.

I have personally crawled under an esarco in amazement to the work that went into it to make it all work. I also had a planned in building one but when i sat down and costed the whole lot it was rather out of my budget. Its like mating two 110 land rovers end to end, so its double trouble on everything! Not to mention i had no real use for it, so it has been shelved.

Good luck if you go ahead, just make sure you post loads of pics when you start the build.

G

[steve b]

There's an 8x8 Esarco not so very far from me , if I get a chance I'll get some pic's

I may even have a copy of the original mag it was first published in - Overlander4x4 - I think ... no comments about age ta

iirc it was 2 front RRC chassis' joined back to back , 'twas a while ago that I read the article and the steering was a mechanical link from the front to the rear

An interesting project , worth another look as it's been a while since the Esarco

cheers

Steveb

[elbekko]

Excellent idea!

I agree on the new chassis - and really, no need for any bends in it, the body will have to be lifted quite a lot to clear the engine anyway, might as well build the whole lot high enough.

You'll have to flip the diffs on two axles, or figure out if you can run the LT230 in reverse rotation, perhaps flip it around and drive it through the PTO hole? (no clue if this could work)

If that doesn't work, you'll have to see what kind of oiling issues come into play when an LT230 is clocked that way. Do share your results, could be interesting for the P38 crowd

You'll need some "interesting" linkages to make the rear steer work fully mechanically, especially as you usually want it to steer independently from the front, or at the very least not as much.

[pat_pending]

Magic mushrooms out early this year!

[FridgeFreezer]

Always good to see someone contemplating a mad project - since it's been done by Escaro you know it's possible so you've got a decent start. They've come up in coversation ghere more than once, there's even a video of one in the video shack I believe. I also recall someone (Bill Van Snorkle if memory serves) giving some good tech about them, plus why they stopped making them, recalled and scrapped most of them, supposedly a bit lethal to drive for some reason.

I think it works out that you don't need to flip the diffs if you use their drivetrain setup because you're driving backwards into the PTO hole of the 2nd LT230.

Simon makes some good points;

1) The IVA is not that scary, a lot of plant equipment used on the road goes through some variant of it and I'd guess you'd have no problem persuading them it's not a family car

2) The LR chassis kicks up over the axles for a reason

3) You're probably best off fabricating your own chassis, or at least just using 2 cheap RR chassis which are 10-a-penny rather than 110/130 which are harder to find in good nick.

4) The drivetrain may need some thought, I like the idea of hydro drive to two axles but I'd be tempted to make them the steering ones. Convert the 2 LT230's to 2WD so the middle two axles are driven perhaps. Not sure what the handling implications are on an 8x8.

Mind you, there was one for sale on eBlag a while back, and while building one would be very cool I can't help but think if there's one out there in need of an owner to keep it going then you may be better off buying a "real" one as it will probably be just as much of a challenge

[tacr2man]

To go with your 8x8 wheel plan your basically going to build a whole new vehicle , the closest you could get to your original idea of a "modification" would be start with a 90 and hang 2 "extra" axles on the back . You could then just use the "foley" tandem drive units . The only things you lose are overall length goes up a bit and you do have a break over angle to consider. You would still need to build a sub chassis to give you a FC ala 11a/11b . But it would be a hell of a lot simpler project. You could still have a crew cab . JMHO

ps You would need to consider a different engine as power losses/ drag would be factor

[FridgeFreezer]

The problem with the Foley approach is they scrub the back tyres due to not having a diff between the two axles, which I'd imagine would get much worse if you hung two extra axles off the back one (and put high loads on the takeoff units). The Escaro avoids this by being symmetrical and turning about its centre.

Volvo 6x6's have a rear diff with a takeoff drive that a LR prop would bolt to, the diffs are quite close dimensionally to Rovers (prop flanges match too) but I'm not sure they'd be a viable prospect price-wise. Then again, the Foley bit probably isn't that cheap either.

[tacr2man]

The foley units are selectable, so would only be in 4wd in normal use, when used in 8x6 or8x8 you dont want a diff in the interaxle hence the difflock function in l/r transmission JMHO

[simonr]

I think the handling was a problem because it had the front and rear wheels steering - which makes it ever so easy to roll while cornering.

Most commercial vehicles with four axles steer the front two.

Another option would be to use shorter springs / shocks on the middle two axles so that on the road, they are only just touching the ground. Or even to make two axles height adjustable so you can lift the middle two axles completely off the ground until you need them.

That lends itself to using hydraulic drive to the middle two axles too as it removes the need for freewheeling hubs. It would also mean that so long as you have a diff between the front & rear axles, the middle two could be driven at the same speed as the rear. The middle two pairs of wheels could be significantly smaller than the outside two and don't need to be road legal or speed rated - quad tyres perhaps? That would remove the need for the chassis to rise up over the axles and mean you could probably base it on a standard(ish) 110.

Years ago, I saw a 110 HCPU at an off road site with an additional rear axle - and was totally amazed at what it would climb!

Si

[FridgeFreezer]

If we're veering off the original a bit, I'd suggest looking at Mr Van Snorkel's 6x6 landy with the articulated rear bogie (a-la Scammel), this sort of layout seems very highly regarded for its off-road ability.

Once again Simon makes a good point about steering, front-axles steering seems to be the popular method for most trucks although presumably the first-and-last method gives a tighter turn at the expense of stability.

[Chicken Drumstick]

There's an 8x8 Esarco not so very far from me , if I get a chance I'll get some pic's

I may even have a copy of the original mag it was first published in - Overlander4x4 - I think ... no comments about age ta

Pics would be great cheers. Where abouts are you in the country? If the owner didn't mind I've love to pop over and have a look at one to see some of the detail not always shown in photos.

Thanks.

[Chicken Drumstick]

I think the handling was a problem because it had the front and rear wheels steering - which makes it ever so easy to roll while cornering.

Most commercial vehicles with four axles steer the front two.

Another option would be to use shorter springs / shocks on the middle two axles so that on the road, they are only just touching the ground. Or even to make two axles height adjustable so you can lift the middle two axles completely off the ground until you need them.

That lends itself to using hydraulic drive to the middle two axles too as it removes the need for freewheeling hubs. It would also mean that so long as you have a diff between the front & rear axles, the middle two could be driven at the same speed as the rear. The middle two pairs of wheels could be significantly smaller than the outside two and don't need to be road legal or speed rated - quad tyres perhaps? That would remove the need for the chassis to rise up over the axles and mean you could probably base it on a standard(ish) 110.

Years ago, I saw a 110 HCPU at an off road site with an additional rear axle - and was totally amazed at what it would climb!

Si

Hi Simon.

Thanks for your comments.

Maybe I can answer some of the other questions posted earlier.

Power I'd probably be looking at a tweaked 200Tdi, it's a stout easily available motor and I'd have thought 130-150hp would realistically be enough, as the production H.U.G.O. only used a 110hp Perkins and the original Esarco's a 150hp V8.

In terms of layout and design, I think I'd probably stick very closely to the Esarco. For several reasons:

-availability of parts

-price of parts

-maintainability of the parts, custom bits are fine, but pricey to repair/replace in years to come

-it works, which would hopefully keep my R&D to a moderate level for a home build amateur.

I do very much like you idea of front twin axle steer. I suppose feasibly you could have axles 1 and 2 steering and axle 4 steering the opposite direction with an override to prevent it's operation at highway speeds?? That way it'd be more stable on road and offer very good maneuverability off road.

Taking your train of thought further with the middle axles. I was thinking off road you'd want axles 1 and 4 to have more droop than the middle two, as when you crest a ridge it would be either the front or the rear that would lift off the ground. On the flip side, the ramp over would benefit from allowing axles 2 & 3 more upwards travel than the others?

--Does this make sense to you and do you agree?

Lastly, I'm very glad I posted this as you have all given me great food for thought and some fantastic info and ideas. Mostly with regards to the chassis, I think it would be better to build one from scratch.

Are you able to give me any pointers on where I could source the material required to do this? I know I can get smaller sections locally, but some box section suitable for an entire 200" or so chassis is rather more daunting.

[TheRecklessEngineer]

How about diesel electric drive?

If you had your engine hooked up directly to an alternator, and then have 4 x motors driving into each diff you can do away with all these horrible cogs and chains and use lovely electricity!

The control side, however, might be a little more complex.