Jamie_grieve
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Posts posted by Jamie_grieve
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Following the requests of a few lads on here to see what happened, here's yet another thread resurrection of the vehicle my Mother calls 'Doomsday Dobbin'..
We left the thread a few years ago with sumb axles bolted rigidly to the chassis and I went back to work overseas. It lives outside as part of the ecosystem in my absence being natural habitat for moss and lichen. I'm not blessed with green fingers but over the years seem to have grown some epic gardens of moss in various land rovers.
On one of my leaves home I decided to try and get some rear suspension happening after I got a wee fright when I thought something broke but it was actually me freewheeling down a hill with the front tyres spinning on the rims with no air at all in them. The front tyres are on 9" rims and the backs on 6" rims. I put the tyres on the 9" wheels without tubes or flaps as the sidewall was enough to keep it up with the 6" wheels. I didn't think of this when they randomly ended up on the front. I do my unimog tyres with an engine crane but these were too hard so I had to make a press to fit them but once mounted they were actually really loose. The tyres are just temporary for mockup. I'll find some real ones at some point, they need to be light. Interestingly it was able to drive some really steep and lumpy ground without any suspension at all and bits of wood jammed in the difflocks. Like a big argocat with really bad steering and no brakes at all. The chassis also flexed quite a lot which was surprising given the construction.
The plan was to continue with the 'low rider' concept and match the rear axle bump height with the front which is 7" higher than standard. The 7" comes from 5" of portal drop plus the larger axle diameter to leave the wheel centre in the same place. This would allow the axles to articulate without lifting the COG unnecessarily. I chopped the chassis for the fourth time after building it and started to graft on some low rider rails.
The material for this came from a local radar station that blew down in a storm. On my previous trip home I helped the contractor chop it up and remove it from site. Interestingly there was a guy from the civil aviation authority there overseeing progress who told us there were about 160 of these installations around the world and only two have ever blown away, both of them at Wanlockhead. The new one has a continuous rating of 200 knot winds so should last a while.
This is the point the build went horribly wrong!!
I had a perfectly functional vehicle that drove into the shed, it needed a bit of welding and some suspension and it could have driven out as an even more functional vehicle.
I started cutting the low rider bits with my brand new tungsten carbide chop saw and huge pile of free radar metal. The saw kept cutting bits the grinder started grinding and the welder started welding bits and before you knew it a chassis rail happened all by itself. Then two rails then my poor landy was in bits all over the place and the cuttoff saw went through the old chassis!
This is also why I was interested in team Idris's current chop as had I just kept welding to the original chassis it would have been out the shed and been a functional toy instead of an almost abandoned project waiting it's turn.
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6 hours ago, Stellaghost said:
Front suspension you are correct I am looking at moving radius arms inside chassis rails and connecting them together at a single point off a strengthened cross member with a rose / creeper joint one I'm looking at has a 30mm fine thread and 30mm bore should be plenty strong going to move shocks inside as well don't know whether to go for single or double each corner picture to follow
The type of springs will you employ may well dictate the amount and positioning of dampers. I also chose to move my airshocks inside the chassis. Moving your shocks inboard will also move your shocks away from the chassis instead of towards (as long as your roll centre is above the axle) it under articulation and is half the reason I did it that way.When stiff enough to prevent excessive roll, they'll also assist with avoiding the front diving under braking. I also employed a one link as you intend to but I used an SU joint from Frogfab in Canada. This is because I wanted 30º of articulation and didn't want anything to bind if something ever broke. The crossmember I made for it is in the picture. The surface area of the ball is quite large. They do compromise ground clearance right in the wrong place but they also protect the front prop, mine hangs down 5" below the chassis. They also allow much greater vertical wheel travel without extending the slip joint on the front prop depending on where you put the joint. Remember your pinion angle at ride height as it will only ever be right once.
A rod end as you suggest with the 30mm shank and bore would be well up to the job as long as the radial and angular deflections are within your parameters. Be careful with creeper joints, they're very strong but have very poor angular deflection at just over 12º each way, not the 40º as advertised.
6 hours ago, Stellaghost said:Had not seen the rakeway conversion but need a Speedo as lightweight is going to be road legal on that note I still have series box from lt77 conversion this would also give me a lot more room but not sure if it will be strong enough
You could always do that digitally with a hall sensor and reluctor off your handbrake or somewhere? I think that three inches will be vital to you, the difference in the angle of your prop at say 20" vs 23" is 1 1/2" of wheel travel at the diff, that might be 4" at the wheels in articulation.
I'm humbled at the interest in my build, I'll resurrect the thread and carry it on from where it left off.
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On 11/10/2018 at 4:41 AM, Stellaghost said:
Suspension wise I am looking at keeping the rear set up but extending it and the trailing arms as I believe I will need to move axle back to allow me to accommodate the longer mog diffs on the front I am looking at single link and moving the radius arms to inside the chassis rails.
The lightweight will probably look better with a slightly longer wheelbase, even a regular 88" needs to be about 91" to put the wheel in the middle of the arch. You'll probably end up with a much longer wheelbase than that to keep decent length props. Remember that as you extend the A frame rearwards that the forces on it become very much greater. The mounting points need to be very robust indeed and ideally spaced further apart than standard. Perhaps you could redesign the chassis to keep it lower for longer and have the a frame mounts on top of the rail before it steps up at the tub outriggers? I made a chassis the width of a land rover one but put holes through it with an oval tube and used creeper joints on the outside of it. The joints were at an angle but had enough misalignment to manage the travel OK. The creepers also have a little bit of give in them also reducing the loadings on the chassis and everything.
Could you tell us the distance from the pinion flange to the centre of the axle on the 404's please?For the front do you mean inboard radius arms or a onelink which attaches like inboard radius arms at the axle but has a central pivot under the gearbox somewhere?
On 11/10/2018 at 4:41 AM, Stellaghost said:At the moment I run a 200tdi and lt77 but considering changing to a 300tdi and r380 box Ashcroft do a stubby bell housing and shaft but was wondering if short defender bell housing and shaft from lt77 can be grafted onto the r380 Will be changing gears in transfer box also
How much shorter is the stubby box than the already stubby 200tdi setup?
Are you familiar with the Rakeway shortened rear output shaft and housing? It'll save you nearly three inches which is probably a lot in that. http://www.rakeway.co.uk/page12.html
Don't shoot me or hate me too much but if you're going to change the engine and box, is there a transaxle setup that would work instead? Obviously it depends if it's going to do any road miles due to the gearing but maybe something to consider that would allow you to leave the suspension more or less as is. Other than the rear trailing arms the rest should be fine with not too silly tyres on.On 11/10/2018 at 4:41 AM, Stellaghost said:Do you have any build threads on your buggies would be good to see maybe knock a few ideas off each other
I don't. the last thread I had was my old stage one which grew a set of sumb portals.
After that thread I made another chassis for it and put a cummins engine in and totally reworked it to the point that the only land rover bit was the windscreen and it wasn't really a land rover any more, so I didn't think it relevant here. I also only got to work on it infrequently as I worked overseas so the thread kinda lost momentum, I only got two weeks off some years but now I jacked my job in maybe more progress will happen with it. Of relevance to the lightweight is that I chose the sumb axles based on the diff position and short diff nose. It uses A frames back and front giving high roll centres to clear the body at 30º of articulation with 52" tyres and to get decent link separation. Side slope stability should be good too but the body will move a lot at speed on bumps.
The other thing I'm working on just now which was supposed to be a wee quick scrapheap challenge type build so I had a toy while the other thing's getting built is a Volvo C304 buggy which I put a chevy v8 in and a most ridiculous front suspension on that I'm frankly too embarrassed to make public till I finish it and see if it works first. It's 6x6 and maybe pivot steer as well. It has an lt95 so almost relevant here but again, I doubt it would be of much interest to many here on a landy forum.On 11/10/2018 at 4:41 AM, Stellaghost said:What are you using buggies for ?
My buggies are just toys, having portals with big tyres and a poor steering lock would make them hopelessly uncompetitive in any competitions these days where squeezing between trees has more value than any kind of cross country performance. They may be suitable as marshals vehicles however as both will have fairly decent crank driven hydraulic pumps and winches.
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What did you make those side rollers out of? They look handy.
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On 11/6/2018 at 8:02 AM, Stellaghost said:
I will try eBay again only kits found up to now we're from America no desperate rush as have axles / halfshafts to shorten at some point could always verifier the thickness and buy some gasket paper thanks for the info DD
How much shorter do you intend to make them? I used unimogs at work, have a 418 myself and numerous friends with older mogs. I don't think I've ever found them too wide under any circumstance I've ever been exposed to. Is there a class of competition you need to conform to that requires an especially narrow vehicle? I understand if it's to fit within the profile of the lightweight. I'm impressed with the machining you're doing. I think you could only work with the earlier series one or two hubs that were steel, the later ones are unweldable.
I've found Atkinson Vos very helpful although they do charge like a wounded bull, I'd heartily recommend AC Price and also hear good things about South Cave Tractors for Unimog parts.
The portal drop will really help your clearance of the body work flexing with big tyres. What are your plans for drivetrain and suspension?
I'm building a couple of portal axled buggies just now so I'm very interested in your progress. -
I'd suggest neither one is interesting enough if he's a collector. The white one you posted has the steering wheel on the left and the green one has it on the right. Which side is good for you?
Give us some more information about his other cars and hobbies and maybe the collective here can come up with some more ideas. Some idea of budget would be useful. I'd suggest an old series one which is very collectible or maybe an ex military one but we can point you in the right direction when you get back to us.
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53 minutes ago, discomikey said:
I don't have enough time to go through and reply to everything right now, perhaps later.
in response to your question regarding what the bulldog actually is, please see below. Its not the best, nor the most representative video of what these cars endure, but it's something.WOW, that thing has some serious engineering in it but it probably has more in common with an aeroplane than a defender. Shame the time lapse was cut short. The Bowler brand carries a huge amount of credibility as they make some awesome stuff but I doubt many have been put to work. Would be like getting groceries in a formula one car. I'm not sure how that thing in the video would fair carrying an IBC of drinking water and a four ton trailer with a drill rig on it on an unsurfaced road? Possibly better than I imagine. The train of thought puts me in mind of the Foers Ibex which in my mind is probably how I imagine the defender should have gone had it been developed. John Foers was way ahead of his time 30 years ago.
I'm interested in your earlier comments about wheel travel. Has the rear wheel achieved full droop by the second picture? It seems massively over damped? Any footage of a standard defender at the same place and speed?
Second time I'm writing this, never ever ever buy a new apple computer, they used to be good, now they're garbage, living on their name, trying to be better, lighter and more efficient than before but made cheap and nasty and failing miserably when you actually need them. Remind you of any other modern brands?
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You'd be as well comparing a panda to a quad bike as far as relevance to the defender replacement is concerned. We had an Audi 90 quattro years ago that had locking centre and rear diffs, it was way better than a defender on light snow and ice.but it's equally irrelevant to a discussion on utility vehicles. Neither a quad nor a panda can carry half a ton of supplies with a team over relatively bad terrain. You can push through surprisingly thick scrub with a defender that you can't do with a quad bike, there's a place for everything.
What we're hopefully discussing here are technical aspects of the vehicle in the spy photos. Many people think of the defender as the ultimate off roader when it just never has been, it's always been pretty carp. It's not that good at carrying things, it's not very well made, the transmissions are made of cheese, the chassis are made from something so thin you could wrap a turkey for the oven with it. They're noisy, slow and uncomfortable. We all know this so why do we like them?
I think Dailysleaze hit the nail on the head with many of his comments.
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5 minutes ago, Anderzander said:
They come with paint on though don’t they ?
Not always, the quote below is from redwinch.
The winch drum is unpainted on the core to support the capstan effect performed on the drum by the rope tightening under load. During trials this has been shown to give a much better long lasting grip onto the drum. A minimum of eight (8) wraps of the drum must be seen on the first layer before winching under load.
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Redwinch on their site advise against paint on a drum. I'm thinking if it was mine I'd give it a coat of that brush on galvanising you get, it's not shiny like paint, it'll stop further rust and it won't care about moisture. It is still a kind of paint but not really if that makes sense. I used it on a bulkhead that's been out in the rain for 5 years and it's still perfect.
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Apologies for the long post with lots of pictures but hopefully most will find them interesting.
2 hours ago, Eightpot said:The number of fatigue failures I've seen on 4x4's in Africa while I've been out in the wilds crossing deserts, long long corrugated dirt roads, smashing through bush etc, is tiny
Just a few of many photos of fatigue failures to show you what you've been missing. This is what you have to deal with in a global market and is what so very few people from the UK ever get to see so I find the perspective very skewed towards crossing a muddy field now and then as to what a utility 4x4 needs to be able to do. Again I would cite the 100m waterproof watch as my argument for having a highly capable product that 95% will never use to capacity. If the people building the car don't get it then what chance has the car got? I've purposely not used the same car twice in any of the pictures. Land Cruisers fair much better in these conditions and is why I generally recommend them but I would love to be able to recommend a British product. The Projekt Grenadier is another I'm following with interest. I also think that by putting forward the illusion of a utility vehicle it will cheapen the Land Rover brand although in the short term it will be much easier and more profitable to build for the masses but I see the problem with the land rover brand that it could quite rightly be accused of talking the talk not walking the walk.
Unfortunately I lost a great picture of a horn bracket that had cracked off allowing the horn to hang on the wire and rub a hole in the radiator which left a team stranded overnight in a place they would rather not have been.
2 hours ago, Eightpot said:Articulation - yes can be useful but not a game changer. My wifes old Fiat panda 4x4 has very little but will run rings round a Defender off road.
Ah, c'mon, now you're just being silly. Lets keep it technical please. Define the individual circumstance in which that happens to have a discussion. Fiat pandas are great wee cars but I don't recall seeing any with any utility companies? The point about the articulation I was making is how it enables a load carrying vehicle to maintain usability and safety in loaded and unloaded conditions not winning some pointless RTI score.
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@ Discomikey, Have you got pictures or video of the car (Bulldog?) You refer to please? I'm not at all familiar with it. I tried a search on here and it also seems to be a brand of off road accessory providers. Is this who you engineer for? Interesting job if it is. A google search was giving me fire trucks.
Some video showing the suspension working would be interesting and possibly fuel for further discussion.I'm keen to use the tractor front axle analogy to continue the discussion. I feel I didn't articulate what I was saying very well.
The point I don't understand is that in my mind the effective spring rate in roll of a live axle vehicle configuration is significantly softer in roll than it is on bump. We could measure this with corner scales and wheel deflection. Were we to put a defender wheel 6" up on a block and measure the load on it under articulation, then with wheels on level ground push the front down 6" (as for arguments sake, I know it won't move that far on bump) we would see a significantly higher load on the same wheel under the same deflection. I understand how the roll stiffness of a live axle can be brought up to that of an independent suspension with the use of antiroll bars. I fail to see how the independent suspension can be made to be softer in roll than bump? This is the point I'm hung up on as I believe the stability and safety to be gained in the scenarios such as the freelander video or the H1 on the rti ramp is what will be lost by the move to independent. I have no arguments about the 95th percentile user who will use the defender replacement on flat grass fields and gravel tracks but that's not why people who can't swim buy 100m waterproof watches.
We surely expect the Defender replacement to be able to cross terrain other vehicles can't and I fail to see how the use of the independent suspension shown in the spy shots with the short arms will achieve this in a durable fashion.
On the bearings, although I used the scenario of a v shaped gully, actually the opposite was normally the case of many of our hub and suspension ailments. Certain types of laterite and mud roads get ruts in them from trucks passing then the ruts get baked in the sun and the light 4x4's end up straddling them for hours. Alternatively just the motion of constantly driving in and out of ruts would take it's toll on the bearings, wheels and tyres. This scenario would also put additional wear on independent suspension joints that a live axle configuration wouldn't see.
We get the same thing in soft sand where trucks leave ruts the 4x4's have to fight and vice versa. We often have separate roads if we can or I ban the light vehicles if it's really bad. This is more to do with getting stuck than a maintenance issue...I digress, sorry.
I have to disagree about the bearing choice however. Shipping overseas is very costly and labour costs are generally very cheap in the type of country that has the poor infrastructure the defender replacement ought to be suited for. I would guess I could land 20 defender bearings for the price of a unit hub with the bearing already in it. You can also change a defender bearing with very simple tools in the field that would be impossible with the type in the upright you refer to. I also think the larger spacing of the old type of bearing was better than the new unit design which has the bearings very close together. Although the radial loading capacity would be the same or better, the axial loading I believe (without evidence as I haven't used them in a fleet role) to be inferior. It's not the current design thats the issue to my mind, it's the design criteria at fault and that they're built for mass production. There's nothing wrong with unit bearings and hubs if sized appropriately but those on the platforms I've seen are physically no larger than the parts found on any modern luxury saloon, same too of the driveshafts and CV's.
Perhaps what I feel is lacking with current designs is that there is almost no additional redundancy in any of the drivetrain components compared to various luxury cars. Surely everything should be twice the size, more voids in larger bushes, more travel, more of everything and it isn't the case.Has the thinking that led to the gearbox choice of the L322 changed at JLR? Why would they put a gearbox in a car that wasn't even rated for the power produced let alone the fact it was going in a particularly heavy car? The weakness didn't show up in the testing and trials, I'm sure the selection process ticked all the right boxes yet there must have been close to a 100% failure rate by the time they had 150,000 miles on them. I'm concerned the same will be the case with the defender replacement.
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Will you be ditching the alrc rules and competition altogether? If so, would you not be better off starting from scratch with a tube frame and transfer all the bits over to it?
I've been cursing working round a chassis after recently starting work on an off roader based on a Volvo C304. I said to myself I'd never build another buggy again with a chassis when I built my last one, this was meant to be a quick scrapheap challenge type build that's now grown legs and I'm regretting it already. Every time I look at it and think of the time I've wasted and compromises I've made instead of just sitting everything on sand bags where I want it and join the dots with tube. That said, I haven't owned it for long, that thing of yours is almost like a pet the time you've had it, would be a bit like shooting your dog if you broke it.-
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Joan Allen http://www.joanallen.co.uk/Gadgets-s/324.htm
does this plastic sand scoop. I think working with a metal one will drive you insane but I don’t know that. A plastic gold pan, a plastic trowel and a pinpointer are my normal detectoring accompanyments. I never tried the beach yet, I’ll be interested to hear how you get on.
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On 10/24/2018 at 2:43 PM, discomikey said:
I don't know your experience/qualification in this area of vehicle dynamics and do not wish to offend you, but from my experience (off road motorsport engineer) I would wholeheartedly disagree with this statement. No offence taken!! If I'm wrong I'm wrong, I relish technical discussion and am happy to learn from someone with more experience than me. My relevant experience is fleet and workshop management for organisations in remote and difficult to operate areas since 2006, I have an honours degree in mechanical engineering. I have been subjected to 15,000 hours of full body vibration operating articulated and rigid vehicles and plant in mines, construction and quarries around the world and have had the xrays and surgery that goes with it.. I used to work as a plant fitter then I spent some time designing and building washplants and equipment in abrasive environments. In short, I've spent my entire life watching mechanical things get beat to death.
Vehicle dynamics is an extremely complex subject, Roll stiffness V.S. ride frequency are not directly linked to suspension type. Geometry, yes, but this does not mean that generalising independent suspension to be worse than live axle in this instance. Fair comment and as I said previously I'm no expert but I made the generalisation based on current norms in vehicle construction and a criteria that put off road capability and maintenance ahead of driver comfort and road holding, I should have been more clear.
Our bulldogs have very similar wheel travel to a standard defender. similar articulation, but better on and off road handling by miles. Roll stiffness and articulation are, in effect the same thing. whether this is tuned through suspension geometry, roll axis height V.S. CoG, or the addition and sizing of anti roll bars, is almost irrelevant.
There is a difference with independent compared to live axles which would need clarified for further discussion in that do you mean vertical wheel travel or articulation? A defender axle moves 9 or 10 inches vertically but perhaps with 16 inches of articulation. Consider a centre pivot tractor front axle, does it have wheel travel or not, it obviously has articulation. Maybe we need to make sure we're not discussing apples and oranges. That said, I would love to be arguing from the standpoint of a defender live axle and suspension with 30 years of continuous development and not just a 50 year old copy and paste from the classic range rover.
You could make a beam axled car with a super low ride frequency and super high roll stiffness if you wanted to, Inversely you could also design a fully independent car with super high ride frequency and super low roll stiffness. Now I have to admit to not having the required knowledge and experience, this is what I obviously don't understand and am happy to admit I might be quite wrong on.
How do you achieve this with typical sprung or unsprung masses and typical sizes of mass produced components? Using the tractor axle above as an example, could you design an independent suspension to mimic that? Obviously it's at one end of the spectrum, but a live axle isn't far behind. The difference in vertical spring rate vs roll stiffness in a live axle in conjunction with or without an antiroll bar is what I believe makes the live axle more suitable for a utility vehicle. If we assume the load on the rear wheels of a utility vehicle to double under loaded conditions but we also want to minimise the loss of ground clearance and maintain load sharing as far as possible on uneven ground I simply cannot see how this could be done as well with independent suspension. If we say that the wheels have a total of 12" of articulation on a bit of rough road which would be each wheel displaced 3" up or down from the road surface, how much would translate into a variation on load on the wheels with live axles compared to an independent suspension in loaded and unloaded condition? On a tractor it would be near zero for example.
I also contend that the increased variation in load on the independently sprung vehicle translates into increased fatigue in the monocoque, an uncomfortable ride on really bad roads as in my picture and a dangerous one when the surface is bad enough to rock the whole vehicle side to side as in the freelander video previously posted. Additionally, with an independent suspension, how do you have a system which if it has a low enough spring stiffness to give the same articulation as a defender then what happens when the design criteria also requires to maintain ground clearance when both wheels at the front or back encounter a bump in a rut? Compromises have to be made with independent that don't exist with a live axle. Obviously much of this could be done using variations with spring rates with air springs but these don't last the test of time in an arduous environment so are outwith the scope of discussion on a durable utility vehicle.
It just depends on what the criteria for the design is.
Exactly!! That's what I've been saying. I realise I'm coming across very anti independent but this isn't the case at all. My argument is that the design criteria selected on the vehicle in the images has compromised the concept that I hoped we would see. Had the lower arm been coincident with the centre of the wheel with portal gearing to increase ground clearance I would have placed an order!! My comments on the live axle are based predominantly on durability and simplicity rather than on superior all round performance. I fully accept that if someone says the wheels need to move 16" then an independent suspension could be packaged to suit and behave better than the same on a live axle under many circumstances.The smaller PCD stands up absolutely fine in extremely harsh competition environments, It's not the wheel studs that take the loads (or at least shouldn't be by design), its the centre spigot. We go through hundreds of wheels on races, every failure is rim deformation. barring one, which was of a defender wheel where the centre ripped out. up to press smaller PCD wheels have stood up to that.
I don't agree that competition is a useful metric or benchmark for defining a harsh environment, there just isn't any competition that lasts long enough to really show up what decades of in service life will. You simply will not see the fatigue cracks in areas that genuine service life will reveal. The cracked wheel I used as an example simply can't happen in the time frame of any competition yet was a fairly regular occurrence. Likewise chassis cracks due to fatigue, spline wear, any driveline wear at all etc. Competition vehicles also generally aren't neglected, overloaded and towing trailers at the same time. How much redundancy is left were the vehicle to be armoured and the weight increased by three tons? Sounds ridiculous but this regularly happens to Land Cruisers and G wagons on standard parts and is what I would consider to be a harsh environment. Remember we're talking about improvements here, not whether a land rover engineer could argue the cause for a debating team the design might just be adequate at best.
I also disagree that the wheel studs don't take loads, I believe (and could be wrong) that the hub spigot on the land rovers is only to maintain concentricity of the wheel during mounting and under extreme duress. You can easily tell if a wheel is hubcentric by the use of flat washers or flanges on the wheel fasteners with a hubcentric design the hub spigot is load bearing but only in conjunction with the studs keeping it there. The wheel also has to be thick and heavy. If the fasteners are conical then the wheel is centred by the studs. If the aluminium wheel on the steel hub were load bearing the necessary movements due to stress and strain would lead to fretting of the aluminium at the spigot contact surface. The different elasticities would be very difficult to accommodate in such a small space. Even if the hub was hubcentric, the smaller diameter is surely not an improvement?Imagine the scenario of a vehicle in a V shaped gulley, how would you describe the tensile or compressive forces at the studs on the top and bottom of the wheel and then the spigot? The point I was making about the pcd is that it was not an improvement in any way and that all of the relevant components are now subjected to higher stresses. How will the smaller pcd perform when two studs are broken for example compared to the old? How much will a piece of debris or rust on the wheel mounting flange affect balance and bearing life? How physically large can the bearings and half shaft be when they have to share the smaller space in smaller components as found in current land rover products.
That was purely spoke design and the cause of impact being 50+MPH into a tree with said wheel though.. the entire chassis was shunted on the left hand side by 25mm. After a 50mph tree strike I think occupant survivability is about the only important thing, let the wheels fall off!! I'm sure improved safety of the new vehicle will be at least one aspect we don't disagree on. I've picked up the pieces from a number of defender rollovers and other crashes that weren't pretty.please let me know your thoughts for this. Healthy discussion of course. And what makes this trickier on independent setups.
Hopefully my above comments satisfy this but I'd also reiterate another topic for discussion if I may, that Independent setups by their natures have more moving parts and are subject to more wear and reduced lifespan due to parts moving through greater angles and distances. For example, if you look at the movement of an independent CV joint compared to that in a live axle.CV joints don't last as long, the bushes or bearings they run in flog out quickly, they are easily damaged and suffer from water and dust ingress. Experience has shown that very small amounts of wear or damage in an independent suspension component will likely result in camber and tracking problems resulting in increased tyre wear and long term running costs compared to live axles. I look at tyre usage on Toyota hilux and ford ranger IFS and compare to those vehicles with live front axles and see an enormous difference. If I look at recommended parts stock levels, workshop hours allocated to the same there are twice the times and jobs on IFS as the live axles. I can only assume IRS would be the same as a few armoured shoguns are all that I've seen with IRS. I understand this is a different scenario to that of a racecar getting fully inspected after every section, a utility vehicle might be lucky to see a hose down once a year. I've purposely left Hummvees out of the discussion as the defender replacement will be too far removed from it to be relevant although lessons learned from it may be relevant.
The discovery 3/4 reigned as tow car of the year for how many years running? That's a very good car from many aspects and I came very close to getting one myself but they most certainly aren't a utility vehicle capable of thousands of hours on corrugations and rough use nor maintenance without special tools by people without specialist knowledge. How often do you have to change the suspension arms and brake pads just in the UK, now translate that to somewhere with very poor infrastructure. There are many simple operations that require the removal of the body such as the timing belt which is quite frankly ridiculous.
I would also argue that our 17 plate ford ranger is noticably less stable, and less grunty than our predecessing D4. For a pickup however, It is lovely and I really like it!
I agree with your choice of vehicle at that price point and caused a storm in one organisation years ago when we got 22 ambulances based on the ranger platform instead of hilux on my advice. Maintenance costs have been lower and cold weather performance has been superior. Have a look at the 'light tactical vehicle' configuration if you buy another one. They are remarkably cost effective and capable. There's a reason they have overtaken Hilux in Australia as the no 1 where Toyota is practically a religion. Comparing a Ranger to a Disco four is surely like comparing apple sauce to an orange tree? -
Likewise you've not responded to my post.
Apologies for not noticing a response was required from my side, a quote would have made it easier to notice or respond to. I was also wondering what folks would say on this hence my original question.
On 10/13/2018 at 7:18 AM, WesBrooks said:'d like to be interested by the new defender but I'd have to say I find the Jimny far more interesting although in balance Suzukis historic efforts on achieving well in European crash and saftey tests appear to be lacking.
Anyhow, at the risk of diverting the subject a little the discussion on roll centres teases my interest. Any recomended reads? Detailed suspension setup seems a black art from brief reads and looks around the the pirate 4x4 site.
My understanding is height of the roll centre (RC) is half the story as it is acted on by the centre of gravity (CG) causing the body roll. CG above RC results in more body roll away from corner. Other way around and the body will roll in toward the corner. I thought road cars didn't necessarily aim for low RC, but a low seperation between the RC and CG to avoid lots of body movement through rapid chicanes or changes in direction - at least until aero concerns start to come into play. Is this the same for off roaders? Isn't the high RC more about matching the high CG due to ground clearance and tall body etc? If anything independent suspension could be better at keeping the RC closer to the CG with variable height?
I'm not an expert but to at least answer you as best I can:
I don't have any recommended reads but I would say that most information on the net concerning roll centres is focused on cars with tiny amounts of (very stiff) suspension travel compared to what we're discussing here so my suggestion is to make sure whatever you're reading is relevant to 4x4's with large wheel movements, soft spring rates and relatively low frequency of response from the wheels.Having the RC coincident with the CoG is the very worst case scenario which would give the worst handling and is normally avoided at all costs on road vehicles but on an off roader would it be so bad? I think it would still be bad as it would be unpredictable. The reason is that if they were entirely coincident, any lateral loads are going through the suspension links in an uncontrolled fashion rather than in a controlled fashion through springs and dampers. Normally most cars have a roll centre below the centre of gravity. The problem with a high roll centre is that any vertical movement from the suspension is also translated into a horizontal movement which will be applied at the height of the roll centre. this isn't a good thing as the inertia of the vehicle will resist this, large unpredictable forces are generated and it's an unstable situation at speed as well. A mix of controlled amounts of roll stiffness with springs, dampers and antiroll bars to deal with inputs from the CoG via the roll centre positioning will result in the desired handling characteristics.
On 10/13/2018 at 7:29 AM, WesBrooks said:Engineers ability to optimise roll centre also hampered by the favoured live axle suspension?
Quite the opposite, it's way easier to get exactly the height of roll centre you want with a live axle, it's the middle of the Watts link, the A-frame ball joint, the instant centre of your four link, more or less the middle of a panhard, etc The roll axis can be easily tuned to suit by variations of the two. On a McPherson strut suspension (as it looks to have on the new defender replacement) the roll centre moves about lots due to the large changes in the angles of the lower arms / wishbone. Optimising the position of the lower arms is where I see the problem with this platform sharing and it's why I asked the question but nobody has answered me. I believe that in an attempt to secure better on road handling and to avoid having the lower arms pointing up from the body to the hub carrier they have instead lowered the outer end of the arms down to favour on road handling instead of ground clearance and better cross country capability. Would the on road handling have been significantly compromised by having a higher mount on the hub carrier? I don't know exactly but I doubt it.
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On 10/15/2018 at 3:18 PM, FridgeFreezer said:
And yes, each vehicle has its weak points but then an FL or D2 or P38 has a lot of strong points over a 90, this isn't about cherry-picking examples where X is better/worse than Y, my POINT is the massive negative conjecture about a vehicle we know almost nothing about, and nay-saying of things like independent suspension with no good reason.
I mean, someone in this thread actually cited the PCD of the wheels as proof it would be totally rubbish, what the hell are people in here smoking?
You can argue with the styling and the complexity of some of LR's stuff certainly but you really can't sensibly argue with how capable it is compared to almost anything else on the market
The reason for the massive negative conjecture about the vehicle we're discussing here is that the next generation of Land Rover Defender (which although not released) has been confirmed by land rover that this indeed is a 'spy shot' of the next defender, so not something we know nothing about at all. We understand there are 4 of these things now. Any more information since then to further shape discussion?
You say the nay saying of independent suspension with no good reason when it's been very eloquently explained to you the main problems with it by others way better than I did in my first post which you didn't respond to. The picture above with the H1 explains it perfectly. I will try to add a little more to help with your understanding. To have a spring stiffness soft enough in roll to allow enough wheel travel to maintain wheel contact with the ground would result in a very low frequency of response from an independent suspension which would not result in good behaviour at higher speeds on rough roads. With a live axle this can be mitigated by using stiffer springs mounted closer together that will still be soft in roll to allow the wheels to move but stiff enough to avoid damage and maintain ground contact when the wheels hit the ground hard or preventing dive too much under braking which can also be enhanced by antidive suspension geometry. Thie same situation with live axles with stiff close springs also allows more weight to be carried without the vehicle sitting on the bump stops but also still allowing articulation, likewise under certain circumstances towing trailers (P38 you mentioned was also a good example of this).
The next problem I haven't seen discussed but possibly I missed it is the dramatic reduction in ground clearance from an independently sprung vehicle both off road on bumps and under braking. A simple dip in the rutted road you're driving on combined with a slight precautionary touch on the brakes will result in the bottom of your vehicle bottoming out in the same situation a live axled vehicle will not. Bottoming out a vehicle in ruts with aluminium suspension arms and chassis will not end well in the long run. The vehicle in the spy shots has particularly low hanging mounting points for the rear arms at the wheels which are no higher than on any conventional passenger car which does not bode well for long term reliable operation in any off highway environment. I welcome your thoughts on these points to further discussion, I accept that it's based on these particular spy shots which is the entire purpose of this post. If the new defender turns out not to be this vehicle we're discussing here then we can talk about that in another post but in the meantime, Land Rover have told us that this is it.I'm the one who mentioned the pcd. Can you explain to me please why or how the smaller pcd could be considered an improvement over the larger defender one? I'd suggest parts bin raiding being the single and only excuse, not to reduce the cost but to maximise short term profit. Not a bad thing, JLR only exists to satisfy shareholders and a smaller pcd does that in the short term. Doesn't stop me whining about it though.
I can give you an example of when a large manufacturer changed their pcd to enhance reliability however. That was Toyota, they changed from the 6 stud to 5 stud larger pcd with thicker studs for their heavy duty applications of the land cruiser when they moved to coil springs. It cost them time and money to implement but it's also why by constantly improving the product they are the benchmark and everybody else is playing catch up. I'm not sure if you appreciate the stress that wheels and hubs go through in the off highway world? Unfortunately, I'm not sure the current crop of land rover engineers do either. If you damaged a range rover wheel on a kerb I'm sure you could forgive it so to speak, not so a defender, I've seen the test videos of the disco 3 on the tiny kerb strike and ditch crossing but we expect a damned sight more from a defender. I added a picture of a typical defender steel wheel with cracks to give you some idea of how defender wheels weren't up to the job before. I'm disappointed they will be replaced with components subjected to higher stresses which arise by making them smaller. I would expect to see cracks not only on the rims but on the wheel discs and more broken studs and wheel nuts working loose. I haven't seen a steel wheel on the smaller pcd yet but it'll be interesting to see how thick they are. Again, your thoughts please. I added a picture of a bent steel wheel which although misshapen allowed a vehicle carrying an injured casualty to be driven to safety which could not be done with an aluminium wheel which would have broken. A steel wheel with the necessary thicker disc for the smaller pcd may well have broken the studs resulting in the death of the casualty. Then you ask what I'm smoking...? I don't smoke, I don't understand why you would include a personal attack on me in a technical discussion. Please use terms like stress, strain, yield point, psi, kpa, fatigue etc in your response to keep the thread from getting personal. Please also respond to any points in my first post you disagree with to further discussion.
We can and are arguing about capability of it in the market, I already stated in the original post that looks were not part of the discussion. Complexity...? Well please tell us your thoughts.I put forward that for the typical fleet user in mining, agriculture, ngo, UN, military etc how the Land Cruiser 70 series can be bought for half the price the defender is being touted at, can be got with front and rear lockers with a 25 year design life with world wide parts and dealer distribution in a variety of body styles to suit the end user with a proven track record in remote areas. It can be repaired by unskilled personnel without special tools and will have a reliability and whole life cost a fraction of the new defender.
I also argue that for the recreational user that the Jeep Wrangler Rubicon will be a better contender with more options to personalise it at a lower cost and that the recreational user has bought a vehicle with real heritage that isn't going to be in the main dealers for repair as often and that it will be on the whole a less stressful new vehicle ownership experience. I'd also suggest that the live axles will give a better cross country mobility and that the end user could easily optimise the suspension and tyres further than will be possible with the new Defender to suit their requirements for enhanced cross country mobility or towing or whatever.
I suggest that the new Jimny will be better in certain rural settings for gamekeepers, estate vehicles, for anybody that wants a small light low ground pressure vehicle that's cheap to buy and run for employees that still has a credible degree of off highway capability, that's easy to clean, doesn't depreciate too badly with a proven track record of reliability. I'm sure there's an urban angle as well with it. I accept it's not a direct competitor but in the all terrain vehicle market with so few vehicles that it will compete in some ways.I reckon any of the Jap pickups will be as capable towing a trailer, putting a pallet of bricks in the back and venturing as far off road as the new defender, I'd also say they'll do it whilst staying away from the dealers for major repairs.
Your thoughts on the competition too please, this isn't someone being right and anyone else being wrong, it's about discussions of global market and technological trends, past performance and such like. I want someone to explain to me how the new defender uses something that makes it more durable or reliable than current vehicles, I want to know if the ingenium diesels are going to suffer oil dilution or not, that sort of thing. I'm not in vehicle development, surely the combined brains and experience here can put my fears to rest that the next generation defender replacement are actually going to be more than the illusion of a utility vehicle, hence the negative conjecture you refer to. Try to alleviate my fears with facts, figures and evidence to the contrary. I actually do buy new vehicles regularly on behalf of clients, I can't imagine buying a Land Rover now after 8 years since being able to buy one (ROW spec). Where would you even go to find a dealer that understood what you were asking for? The picture of the road is very typical in many areas of operation the defender replacement would find itself. Many places have thousands of miles of these roads as the only infrastructure. Now can I add three tons of armour to the stock suspension and drivetrain components and get very few failures like a Toyota or Nissan? There is no similar terrain in the uk, we don't drive off road in the proper sense that gives rise to so many issues which is possibly part of land rovers problem being so uk-centric, especially since all of our opencast mines closed down which were a real test. Please keep this in mind with your responses.
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I suppose most have seen the pictures of the new defender released yesterday.
It's a defender in disguise as opposed to a range rover based mule. My first thoughts are:
I'm disappointed.
I'm not surprised.The defender has always been the result of parts bin engineering without any bespoke important parts, we should not be surprised that the new defender is a rehash of current / future cross platform suspension, drivetrain and major components. I was rather hoping this time it wouldn't just be borrowing bits from an old range rover and sticking a new badge on it. it's being treated as the younger brother getting the hand me downs rather than the head of the family from which brand respectability comes from. People expect off road prowess from a defender, the platform shown here will be sadly unable to provide that any better than any of the current offerings. I think we can safely assume it will have locking differentials and traction control but the length of the suspension lower links and the very low outboard positioning of them at the hubs means that regardless of ride height it will be unable to move in deep ruts and that suspension travel will be very restricted as it is on the current vehicles. The tiny pcd of the wheels points towards equally tiny driveline components, unit hubs and a restricted gvw way below anything that might be considered heavy duty.
I'm also disappointed to see they're testing it on low profile road tyres instead of optimising everything for more aggressive tyres with at least an 80% aspect ratio. The positioning of the lower control arms very low also looks like the minimum wheel size might be larger than those sizes for which proper off road tyres can be found easily. I hope a 16" wheel fits. Try buying an off road 17" tyre in Africa or the Middle East. keeping the pcd and tyre size the same would have made more sense from a fleet user but less sense from a parts bin perspective.I'd hold any judgement on the looks until we see one in the flesh but one concern if the body has some semblance of the real thing would be the depth of the doors based on the absence of sills which is a real failing as exists on the likes of the new Disco 5. It's a bit embarrassing if you cant open your door next to a high kerb to drop the kids off at school or if your stuck in snow, heaven forbid you took one of these new Defenders off road or in the mud and found yourself stuck and unable to open the really low doors because you were high centred. The high door bottoms on the old defenders were actually very practical and they were generally out of harms way and allowed one to drive over stones and such like with the wheels to avoid potential damage to other parts.
The very low rear mounted silencers look very vulnerable and whatever is under the passenger side footwell looks really thin and ready to get ripped off.
Competition: Toyota, Jeep, Suzuki, Jap pickups. I'm not really sure why people are choosing to compare the Defender with the Hilux when the obvious and natural nemesis ought to be the Land Cruiser 70 series but in recent years as the Hilux improved it became the competition and the Land Cruiser moved on into a different league on its own years ago, even before the 4.5 litre v8 diesel became an option. The Land Cruiser is the benchmark against which we should be comparing the rest of the utility vehicle market. Jeeps are only recreational vehicles, they're not a choice for fleet purchasing. The Jimny is an interesting one and is actually well suited for fleet purchase.
That being said, Jeep had a fantastic stand at the Geneva motor show this year and really showed the brand and heritage. The Land Rover stand was dull, bland, you couldn't talk about utility vehicle fleet sales and every single vehicle was on low profile road tyres which shows how the brand wants to project itself. I'd have no doubt the Jeep rubicon with live axles and differential locks coupled to its robust but simple driveline and build will leave the new defender for dead in the mud and reliability stakes for a recreational user and offer much more in terms of post purchase upgrades to suit the individuals requirements.Regarding trailer towing, all the Jap pickups tow 3.5 tons now as does the new Merc pickup. One worry is if this new Defender is as light as they say it is then it'll be very unstable towing a fully loaded trailer and struggle on drawbar pulling tasks like recovery or dragging things. Sometimes you actually want a bit of weight. It's kinda why you don't get skinny rugby players, the new defender seems like a bit of a ballet dancer or chess player in its construction whereas the Land Cruiser would be in an All Black's scrum.
In my mind there is no question that live axles are better at crossing a wider variety of terrain safely and more reliably year on year. I can't think of asingle reliable fully independent suspension in a 4x4 commercial vehicle with the possible exception of the humvee which needs a lot of maintenance.. Things like the Shogun don't count as they're not really commercial load carrying vehicles.The cost of tyres on a misaligned independent suspension and extra maintenance costs changing bushes and links is significant as is the extra downtime. A failed bush in a live axle suspension will not deteriorate the system effectiveness significantly compared to an independent system which will be seriously compromised with even just one bush failure.
Accident damage is also more likely to prevent an independently sprung vehicle from either limping home or undergoing successful repair.
The independent system shown in the pictures has fairly short arms and assuming there is some kind of suspension travel beyond that of a normal road car then the bushes are unlikely to last long on poor and unsurfaced roads.
The old defender was c rap off road in cross axle circumstances but it would generally get the occupants to their destination day in, day out unlike the modern JLR products which are not only unreliable but impossible to fix without specialist knowledge and tools. The current JLR vehicles do not have the real world ground clearance, approach, departure and breakover angles of the defender which are the cornerstones of all terrain prowess (despite what marketing and traction control would have us believe at the land rover experience). The very weak defender drive train is what should have been picked on and improved and the crash safety and corrosion resistance.
Easily replaced panels is the only thing that kept my previous defender fleets competitive with land cruisers which would generally have to get written off after an accident involving major bodywork repair. Being able to scavenge body parts in a Frankenstein fashion made defender fleet ownership really quite viable. I wonder what the advantage over other brands the new defender actually has?4x4's need a high roll centre to operate safely off road, a low roll centre encourages body roll and is less stable on side slopes as well as giving poor traction on climbing obstacles as the wheel tries to pull away on contact reducing grip.I'm not sure how the roll centre of the new defender has been optimised over that of other vehicles which will share the platform. It's almost certain the platform will have been designed with the lowest roll centre to suit a road car as much as possible.
I think what we're looking at here with the new defender is an illusion of a utility vehicle. Why build cheap with a small margin when you can spend a tiny bit more to get better than the predecessor and (which will be so easy to pick parameters the new version is better than) sell at a premium. Building a premium vehicle cheap is very difficult but Toyota has managed it. You can get a Toyota 70 series for $25k, I'll probably keep buying them then, shame, I would love to buy a British vehicle one day. -
That thing is amazing and the work you have put in is epic.
How do you intend to get the front winch rope to lay properly after exiting the winch rope pipe in the chassis? Does something after the end of the pipe move as it lays or is there a fairlead type arrangement or doughnut to be added? How far is the winch from the end of the last unmovable guide? Where is the front winch in relation to say the three bolts for the gearbox mount or any other handy datum?
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The side of the chassis at the front has a large number of mounting holes, originally these have pressings that do a similar job to crush tubes. If these holes are used they shouldn't be able to allow anything to move. The steering box holes are the strongest part of the chassis at the front, the lower ones on the outside are a good mounting point. Some chassis manufacturers neglect to put these in so it's possible the holes in the chassis have elongated when the sides have crushed a bit and the bolts have become loose.. First job is to strip the whole front end off and see what you're dealing with and make repairs easier. A few pictures of what you have may help with better suggestions based on what you have. Welding crush tubes in would be a start and not do too much damage to the chassis.
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Another option could be to find another chassis with stronger axles than land rover ones that you can put the series body on.
This is the route I'm going just now although I think it's going to turn into an off roader instead of a road going vehicle.I think you would really regret not using your LS1, it is so flexible, light and easy to work with if you have all the bits. If you want a 109 wheelbase then you have loads of room to divorce an lt230. Rakeway does a shaft for £235 plus vat (it was in 2016) then you can use any manual gearbox that just bolts up to the LS1. I used a Volvo 6x6 chassis which already had portals and lockers , RH drop and the same flanges and is a mild steel fabrication so easy to work with.
I wouldn't contemplate landy axles unless you fill them with Ashcroft goodies. Not needing a fancy adaptor and using a remote transfer might free up some cash for them? Then a 110 chassis and an old disco would have you most of the way there. You could look at Nissan Axles too as they're strong and an easy fit.This might give you some inspiration. Your intended use might help us to suggest alternative chassis or running gear.
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1 hour ago, steve b said:
I like your bench under that engine and box Jamie
. Did you need to do any re-balancing of the diesel flywheel for the V8 ?
cheers
Steve b
The short answer is no.
However, that's a more interesting question than it seems.
The 6.2 diesel's are externally balanced and failure to do this is the main reason for the cracked webs and broken cranks they're famous for.
It was a kind of bodge last time with the diesel where I just bolted the normally balanced flywheel like it would be for an internally balanced engine bolted to the externally balanced flexplate and crank of the diesel. I didn.t like it but it worked fine for years. I would have no idea how to balance a flywheel for an externally balanced engine.
The flywheel is 25kg and it's centralised on the LQ4 crank as best I can but it hasn't got balanced whilst mounted and it's a lot of weight to get out of hand. It was fine on the lathe turning the recess for the bit of flexplate. There's loads of runout on the ring gear somehow, about 0.030", I think the flex plate wasn't round to start with!! Well, that's what I would like to think, I'm sure I wouldn't put a wobbly bit on a spinny bit on purpose.
Well, I did add a little bit of unbalance with the drilling of the bolt holes for sure, two of them coincide which was nearly the end of the project before it started then I thought that I've seen far worse and how bad could it be so I carried on.
I would also like to use a fluid harmonic damper pulley on it and a shaft for a hydraulic pump. I'm not sure for how long I'll live in fear of the flywheel jumping up and landing on my lap like a pussy cat or just chopping my legs and hands off before spinning off into the distance. I have a megasquirt ecu coming this week and I'm hoping to get it to idle nicely at 500rpm with enough inertia in the monster flywheel to get over something like a tree stump at idle.
The picture shows the crank spacer used with the 4L80 E auto to put the flex plate in the same position as a sbc which is what allowed me to think to use the diesel flywheel which shares the sbc pcd and backspacing. There is a ring over the crank spacer too as the spigot for the flywheel to crank is bigger on the sbc configuration.
I did it without any knowledge or connection to the chev world which made it more time consuming and getting it to run has been a steep engine specific learning curve which is about to get steeper with megasquirt which I've never used.The bench is really handy as it can roll around the place easily. Future improvements include proper drinks holders which it currently lacks.
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I started with a flywheel from a 6.2 diesel that I had already and had been mated to an LT77. I used a spacer that comes with the 6 bolt flexplates for the 4L80 auto and made a little concentric ring to centralise the flywheel exactly on the crank. Redrilled the bolt holes as the pcd is different between sbc and LS.
The other thing that nobody knows and probably the most useful piece of advice I can give is for flywheel bolts. They’re M11 and nobody sells bolts for anything other than standard fitment. I used BMW head bolts which were perfect.
i used the 168 tooth ring and outer bit of flexplate bolted to a recess turned in the back of the flywheel.
spigot bearing is different too between sbc and ls. I found a really common one from a lawnmower that worked, was all standard sizes.
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I put an LQ4 on an lt95.
now that photo bucket died, how do we put up pictures?
. Did you need to do any re-balancing of the diesel flywheel for the V8 ?
Engine and Component weights
in Modified Vehicle Builds & Special Projects
Posted
A sumb front axle complete with brakes is 324Kg. add some 16.00x20 Michelins with Daf wheels (why would you?) was 752Kg.
A cummins 6Bt is 480kg with ve pump and SAE3 flywheel housing. A 6Bt with P pump and SAE2 flywheel housing is 520Kg.
An LT230 without handbrake or oil is 48Kg
An Eaton 6 speed with hydraulic PTO is 202Kg
A weight I stole from the Bader site for one of their 404 axle builds at 205Kg
An LT95 with 101 bellhousing plus winch pto at 142Kg
A front of a C304 Volvo with no rear body on it at 986Kg
An A4 Audi quattro gearbox at 78Kg.
I can update a TRM2000 rear axle at 335Kg and not the four hundred and something as quoted by a website somewhere.