Tom A

That would be 70/311/EEC as last amended by 1999/7/EC. EC motor vehicle regulations are aligned with UN Regs (UN regs used to be known as UN ECE regs. The ECE stands for Economic Commission for Europe). The only caution I'd give is that these are the regulations that the major motor manufacturers must comply with. Whether the average fettler can go to an IVA armed with a copy of this reg and demonstrate full compliance is another matter entirely.....

Wikipedia seems to have the answer for the Citroen SM (it did retain a mechanical link) and I think I have the answer to the wider legal question. There's nothing in C&U about the need for a mechanical link but there used to be a requirement in UN Reg 79 (and the equivalent EC regulation) which governs all passenger and goods vehicles in the EU. However, with the progress in electric steering systems and driver aids, this has been relaxed. The intro to Reg 79 has a pretty good explanation: "The intention of the Regulation is to establish uniform provisions for the layout and performance of steering systems fitted to vehicles used on the road. Traditionally the major requirement has been that the main steering system contains a positive mechanical link between the steering control, normally the steering wheel, and the road wheels in order to determine the path of the vehicle. The mechanical link, if amply dimensioned, has been regarded as not being liable to failure. Advancing technology, coupled with the wish to improve occupant safety by elimination of the mechanical steering column, and the production advantages associated with easier transfer of the steering control between left and right hand drive vehicles, has led to a review of the traditional approach and the Regulation is now amended to take account of the new technologies. Accordingly it will now be possible to have steering systems in which there is not any positive mechanical connection between the steering control and the road wheels." Link to reg 79 if you want full details - http://www.unece.org/trans/main/wp29/wp29regs61-80.html I'm not sure if IVA / your local MOT tester is fully up to date with this yet!

If you don't need cordless then I just acquired one of these: http://www.amazon.co...duct/B0039BQRUO to persuade a stubborn crank pulley bolt to come off. Worked very well but it is quite a big and heavy beast. No idea how durable it will prove to be but the build quality seems reasonable.

No car molesting going on, just a weird old house with a garage right next to the office/dining room/general dumping area! Added a few more pics (and removed that bit of white rag), not sure if they're much more helpful....

Nige, Just put a few pictures on my Flikr page for you - basically unmolested 90 50th Anniversary so 4.0 GEMS engine. Bit tricky getting any decent shots of the coil packs, let me know what angles you're looking for as the car's only 5 feet from my PC. Tom

Top weekend - thanks SLRC. A few of my pics: Tom

A few of my pics here: PM me if you'd like any of them at hi-res

Nige, oil is for lubrication; water is for cooling - its specific heat capacity wins every time. If you've got a correctly designed cooling system, the only thing an oil cooler really does is create additional opportunities to rapidly lose engine oil and destroy an engine! You might need to consider one for the poor transmission that's got to handle this engine though.....

At the risk of starting an almighty thread hijack, the more flow does not equal more cooling myth is erm, a myth*. To have it explained more clearly than I probably could, take a look at this page. Nige, there's some other worthwhile stuff on cooling system design (albeit for a LS3) that might be of interest too..... *well ok, ignoring aeration and cavitation and not worrying about pumping losses

Here are mine Warning. Unedited - contains sheep and nose picking.

Actually a Duro does have portal boxes but you're right, you can bend the dead axle beam up and gain extra ground clearance easily. Duro rear axles appear to be controlled by Watts linkages and trailing arms, not sure about the front. I reckon something like this should be slightly easier to fab than a independent suspension setup, particularly if you use something like a Jag XJ diff complete with inboard discs (basically a Dana 44/Salisbury centre section, look here: http://dazed.home.bresnan.net/JaguarIRS4.html )

Interesting topic, I'm also very interested in opinions on scrub radius, ackermann, camber and toe change etc. on off-road racers - not an area that seems to have much written on it except "use what works on a road car but don't sweat the details so much" - mainly because I used to prat about in Pinzgauers that clearly don't have ideal geometry but always seemed to work pretty neatly. Anyway, as Will states, you can't beat indi as speeds increase but something I've always wanted to see done, and might be perfect for the KOH/XTC style competitions is the Mowag Duro approach - De Dion axles and a roll-stabiliser that still lets the axles articulate (a rather clever thing looking a bit like a longitudinally mounted anti-roll bar). Unfortunately I've never been able to get a decent look at the dirty bits of one but I do have the attached pics which at least show how the De Dion part works - you won't get a lighter axle that retains the advantages of a beam...

The next common size up is 255/85R16 (just over 33inches) or a 285/75R16 (just under 33inches). The 255 section width is only available from a few manufacturers - luckily for you BFG Mud Terrains are one of them. However a lot of people will go straight from a 235/85 to a 34 or 35 inch tyre, as this is what most other people are running around on, particularly for competitive off-roading and otherwise you just get hung up in all of their ruts. You'll need a ~2inch lift and probably want to consider lower (numerically higher) diff ratios once you start getting above 32inch diameter tyres; as the opening thread stated all T-cases have the same low ratio gears so you're starting to get a bit overgeared for hill descents otherwise.

Well, I've now read through regulation 25 "Tyre loads and speed ratings" several times - it's a fairly long and complex section but I can't see any mention of speed rating for replacement tyres. It's mostly involved with load/speed capacity of goods vehicles, load ratings and marking of tyres and derogations/exemptions for all sorts of specialist vehicles (electrically propelled, agricultural, municipal etc.) If I'm reading it right (and I'm a remedial reader of law at best, so there's a good chance I'm not) then it probably would come down to interpretation in court - I suspect the critical phrase is in reg 27 para 1 "...a wheeled motor vehicle...shall not be used on the road, if - (a) the tyre is unsuitable having regard to the use to which the motor vehicle...is being put or to the types of tyres fitted to its other wheels;" The Rover SD1 case mentioned would then be crucial, since it would determine whether the courts side with the argument that replacement tyres should meet the same specification as originally type approved or whether a lower specification is acceptable "having regard to the use to which the vehicle is being put". From the anecdotal evidence in this thread it would appear the former is the case. This is not the same for load ratings by the way. Here reg 25 is clear: para 5 "..the tyre, as respects strength, shall be designed and manufactured adequately to support the maximum permitted axle weight for the axle" so you definitely can't use a similar logic to fit under-rated load-index tyres just because you're not using the full load capacity of a vehicle. Usual disclaimer: I reserve the right to be utterly wrong about everything written above!

Sparg: you'll have to check the speed rating of your particular tyres, they vary quite a lot. Attached (hopefully) is a table that decodes the speed rating that's on the sidewall of your tyre. Go and look for something like "116 Q" embossed on the sidewall somewhere near the tyre size designation. The 116 is the load rating (1250kg in this case) and the Q is the speed rating of the tyre (160kph or 99mph in old money) The law is that the speed rating of the tyres fitted must be greater than the declared maximum design speed of the vehicle they're attached to. I've no idea what that is in the case of a Defender but I suspect it's why there's a limiter on the new Transit engined versions, so if someone knows what speed that is please post.... I'd be extremely surprised if any copper could make a charge of incorrect tyre speed rating stick if you'd uprated the engine - the maximum design speed is declared by the original manufacturer during type approval and there's no regulation that changes that value for modified vehicles AFAIK. No idea about hybrids and heavily modified vehicles unless it's assessed during the SVA/IVA process? Hmm, probably need some sort of legal disclaimer here - erm, everything I've written above is the result of a troop of monkeys randomly hitting keyboards and should not be taken as evidence of intelligence, let alone legal guidance.