Dave W

How about Marix Panther, they do a 255/55/18 according to their web site. i use their Puma pattern on my Defender and been very happy with them, good balance, good grip. I'm going to fit either Marix Panther or Cruise to my Range Rover this year as it needs a new set. http://www.newlifetyresonline.com/index.php?main_page=index&cPath=28

Assuming those regulations have been adopted they would suggest that it is possible to get full hydra steer approved. The amount of control required should the "energy supply" fail is defined as: Which the correct steering valve type with the mechanical pump built in should be able to comply with. The only potential snagging point in those regulations I can find is with the requirement (for approval) for a warning signal in the event of a failure. Whilst it does say that: For "full-power steering" (which is what hydra steer would be classified as) though it may be necessary to include a pressure warning switch that lights a warning on the dash should the hydraulic pressure fail. (See section 5.4.2. Special provisions for full-power steering equipment ). That should be simple enough to implement anyway with an adjustable pressure switch in the line from the pump.

The legal aspect is important to me too. My initial understanding was that hydro steer was not road legal BUT the only evidence of this amounts to "hearsay" on forums with no reference to the actual legislation or documentation that would back it up. I've spent some time looking at it and have not been able to find any legislation at all that would make such a system illegal for use on UK roads. The legislation and guidelines that I have found so far primarily cover the condition and operation of the steering components that are fitted. I have not found any legislation or even guidelines that would prevent hydro steer being fitted to a road legal vehicle providing the ability to self centre and control the vehicle when the engine is stopped is met. I'd prefer not to get into further swapping of "hearsay" but if anyone has references to specific regulations/legislation or even guidelines that would make such a system road legal or not, it would be very useful in the decision making process.

I've seen this quoted before but try as I might I've been unable to find any such piece of legislation that would apply to a hydro steer system that can still steer without hydraulic assistance. Do you have a reference for this regulation/legislation ?

Thanks for all the responses, the link to pirate4x4 was really useful, can't believe I've not found that before, it cleared up a LOT of the misconceptions I had picked up. I hadn't understood before how the steering could work without the pump but the inclusion of a "manual" pump in the steering valve makes a lot of sense. Is there actually a specific regulation for that ? I've not been able to find any mention of it. The only relevant regulations I have been able to find regarding C&U, MOT and IVA are the requirement for the steering to self centre and the requirement for the steering to function without assistance (the engine turned off). The more I read about it it seems that providing the steering valve is of the correct type it will meet both of those requirements. I have not been able to find any requirement for a mechanical linkage as such. Any pointers to the appropriate legislation to the contrary would be a great help as that would have a major effect on the decision.

A growing number of challenge vehicles, especially in the UK seem to be moving towards full hydraulic steering or hydra assist steering. I can understand some of the benefits but I'm trying to figure out what the limitations are in the way they behave. So, if you have first hand experience of either full or hydro assist could you answer a few questions regarding their use... preferably with some indication of the supplier so I can compare prices. 1) Does the steering self centre at all if you're travelling at, say 20MPH on a firm surface ? 2) If the engine stops running for any reason, how much control do you have of the steering and for how long ? 3) Do the systems have a failsafe - if, for example, a hydraulic pipe to the ram was damaged would the steering simply remain where it was, force the steering to full lock or centre the steering ? 4) What pressures do the systems actually run at ? (Some of the pumps I've been looking at give a maximum pressure but not really an indication of the actual pressure they run at normally).

Looks like I'm going, SWMBO has made a shopping list...

They are a specialist tyre that uses a softer compound than you would normally use giving the tyre better traction, especially on rocks. Most of the big off road tyre manufacturers can supply them, Maxxis, BFG. Goodyear etc... Outwardly they use the same pattern as "normal" tyres but, depending on the manufacturer, they have additional markings to show that they are the "sticky" version. They are not "road legal". I believe the compound they use is similar to the compound that drag racers use.

I don't claim to know the full details but the way it was explained to me was that they were allowed to compete but were warned that, should they place well, they should expect protests from other competitors. Scrutineering at most motor sport events (including UK) covers safety aspects but it is the competitor's responsibility to ensure their vehicle meets eligibility and safety regulations. Generally speaking on matters of eligibility the onus is on other competitors to raise an objection by lodging a protest with the event stewards (or their equivalent) unless the event has a specific eligibility scrutineer such as happens at some single marque competitions (Formula Ford, for example). Any vehicle that finishes in a podium position is bound to come under scrutiny by both officials and other competitors and in this case the protests were lodged around the steering and, probably more importantly, the tyres. "Sticky" tyres are not allowed in that particular competition and their "illegal" use would give a major benefit to any vehicle that did use them, particularly when the rest of the vehicles did not. Jim and Wayne may have been able to stave off a protest regarding the steering but the tyres protest was the clincher from what I can gather as that gave them an obvious competitive advantage. I have a feeling, though I could well be wrong as it's a few years ago, that Wayne was one of those who lodged a similar protest following the 2007 Outback Challenge when the winning team were judged to have been in breach of safety regulations that gave no real competitive advantage. That protest was correct IMV, as were the protests in this case and I think both Jim and Wayne accepted and probably expected it. In hindsight, pulling up short of the finish line would have been the best outcome but hindsight, as they say, is a wonderful thing.

What's to discuss ? There's plenty of discussion elsewhere, no need to plaster it everywhere. What the hell, my 2c given that you broached the subject... I've no idea if "winning" the everyman challenge was an achievement or not because I wasn't there and I haven't competed in it myself. As far as I can see they were running a vehicle that had major advantages over the opposition that nobody else was allowed to have. They used that advantage to finish ahead of everyone else but were then disqualified as expected. I feel sorry for the guy that eventually was announced the winner because Jim and Wayne "stole" his moment of glory on the finish line. From what I can see in the run up to the event and the KOH event itself they drove the vehicle too hard and killed it resulting in a DNF. It happens but hardly something to shout about. I'm not even sure that they completed a lap ? It hardly takes driving skill to f**k your vehicle on the first lap, pretty much anyone could have done that and many did. The hard bit is judging how fast you can drive without breaking your truck in the process. Good on Jim and Wayne for giving it a go but let's keep it in perspective. Sorry if i seem a bit harsh but it's been bothering me and I needed to get it off my chest with all the sycophants fawning all over the forums and Facebook !

Assuming from that that the ECU has been ready configured in hardware for the map switch, you can find out if it needs a switch to earth or a switch to 12v by measuring the voltage present on pin 3 of the DB37 (SPR1). If there is 5v present on the pin then it should switch to earth, if 0v then it should switch to 12v BUT if in any doubt at all you need to ask whoever built the ECU because if that sticker is wrong and you stick 12v into the ECU you might damage it. In the software configuration you need to tell it which map(s) you want it to switch to when the input is triggered. You can set up spark only, fuel only or both. On the fuelling you can also set a changeover period which is especially useful on an LPG setup.

I think the worst damage I've done to my own vehicle in nearly 20 years of off road motor sport was when I sheared the main shaft in the steering box, this was followed by further major damage to the heavy duty drag link and underside of the vehicle by some moron of a "marshal" with a hydraulic winch who wanted to show off how fast he could winch a vehicle over tree stumps despite being told categorically that he was only there as a "safety net" in case my winch line broke as I winched myself backwards up a steep slope without any form of steering. (The first and certainly the last time I do a CSW event !). I've not seen much in the way of bad damage off road, perhaps because most of the events I've taken part in over the years aren't speed based events. The majority of off road damage is low speed because the vast majority of off road events are low speed so even when things do go wrong the damage is normally minimal. I've seen some amazing damage done to Land Rovers on the road though, usually by people who assume that all Land Rovers travel at 10MPH so pulling out of junctions in front of them is a good idea. Axles, chassis and chassis outriggers bent due to people who decide that their Corsa will fit through the gap as long as they go fast enough.

Not with the 4 bolt box, no. I think that even the Disco 2 box used the same fittings.

You need to take a close up photo of the steering box end of the pipe. There are two different thread types (imperial and metric) and determining which you have will be necessary to determine the part number if you can't find/read the yellow tag. They are easy enough to tell apart from the shape (the metric fittings use an O ring and a flat seal, the imperial ones use an olive style fitting. Most 4 bolt boxes are metric BUT not all, there was a changeover period where they used the 4 bolt box with the earlier imperial 3 bolt pipework, even the bolts through the chassis were imperial. Having said that I've never known anyone manage to strip the threads... maybe you have an imperial 4 bolt and a metric pipe ?

They look like standard V8 Disco or RRC pipes. The long straight section (one of yours is slightly bent) on each runs along the inside of the front cross member with the pipe without any fittings going to the reservoir (mounted on the LHS next to the radiator) and the other going to the power steering pump. The reservoir has another pipe that goes to the power steering pump.

If one or other of the wheel boxes has jammed it'll be because the guide that is supposed to hold the rack (official name for the cable/rod thingy)against the wheel box gear has bent down or worn away. Either way you need to replace the wheel box and possibly the rack. You can replace the rack as described but if the wheel box guide is bent/worn it'll only be a temporary fix. As it's such a PITA to change either of the wheel boxes, I'd suggest changing both of them out while you're there as you'll have to take most of the dashboard out to replace either of them, especially the driver's side one.

OK, I'll start off by saying I'm very much an "interested amateur" when it comes to all things aerodynamic, this is all based on other people's research that I've picked up over the years ! You may want to skip to the last sentence of this post if walls of text offend you To get air flow through a radiator you need a higher pressure at the front of the radiator than at the back. It's a common misconception to assume that the "ram air" effect is enough to cause that pressure imbalance. The faster you go the more air is forced through the radiator ?, no. The only way of increasing air flow through a radiator is by increasing the difference in air pressure between the front and rear of the radiator. Badly placed vents often improve under bonnet temps at low speed allowing convection to do it's job but as you increase speed the exterior pressure increases, causing air to move into the engine compartment through the vents, effectively increasing or balancing out the under bonnet air pressure. In simple terms every bit of air moving in through the vents reduces air through the radiator by the same amount. It is even possible to reverse the air flow through the radiator with badly placed vents at the bottom of the windscreen, even at very high speeds. Cutting holes in the rear of the bonnet curve is probably the second worst possible place to put vent holes, second only to the trailing edge of the bonnet near the windscreen. They will work fine at low speed thanks to convection but as they are in a high pressure area the faster you go the more they will increase the under bonnet pressure, reducing air flow through the radiator. Being at the highest points in the bonnet gives many people the misconception that they work really well because "when parked you can really feel the heat coming out of them". The reality is that that is just convection doing it's thing and bears absolutely no relation to their effect when the vehicle starts moving and you move from basic thermodynamics to aerodynamics. Car manufacturers position fresh air vents in those positions and engine air intake scoops are often sited there too because when the vehicle is moving those points of the vehicle are high air pressure spots. Ask yourself where Land Rover sited the engine air intake for the TDi and TD5 Defenders ? I doubt they'd deliberately position an engine air intake in a low pressure area, although granted I wouldn't put it past them so maybe not the best example Normally the lowest pressure areas are around the front of the bonnet, not the rear. The best position for a cooling vent is normally just behind the radiator with the vent having a lip at the front edge that reduces the pressure even further immediately behind it. You can see the effect when it's raining and you're travelling at highish speeds in a Land Rover, watch where the water seems to form a pool just behind the front edge of the bonnet. If you look at a lot of track saloon car designs they often have the rear of the radiator completely enclosed by a duct that exits through a slot just behind the leading edge of the bonnet. A lot of that is for handling performance reasons (avoiding hot air being routed under the car) but it also improves radiator air flow ensuring a good pressure differential at high speeds. In short, cover up the vents, take it for a spin and see if it helps, you never know

Vents in the wrong place can reduce airflow through the rad, especially as you increase speed. Have you tried covering the vents ? You need a low pressure area behind the radiator to get a decent airflow, adding vents can increase the pressure at speed, reducing airflow through the rad. Steering guards can also cause similar problems as air leaves the trailing edge of the guard and circulates upwards onto the rear of the radiator.

I did run it with a normal defender TD rad for a short time (a week or so) but only because the Ali rad was delayed so it was only ever a temporary fitment and it was only used for running the engine up in the workshop. It was noticeable though that with the ali rad the time between the fans switching on and then switching off again when idling in the workshop, was a LOT shorter than it was with the traditional rad. I got the rad made up by a local radiator specialist, can't remember the exact prices but it worked out cheaper than the alisport one and included the two fans. It uses a much wider "mesh" than the original rad too and it seems a lot less prone to clogging with mud as a result. One thing I will admit to as it was a bit of an own goal, it's worth checking before spending loads of cash on a new rad... I have had overheating problems when moving at low speed. It only occurs in certain rare circumstances, sustained 10MPH crawling. I'd thought it was the fans as as soon as you get over 30MPH the temperature rapidly drops. The solution was much simpler and cheaper but took a while to figure it out. In short the way we'd plumbed the heater in was actually detrimental to the coolant flow through the radiator, something that was revealed when i got myself an infra red thermometer/laser thingy which showed that the water at the top of the radiator was actually cooler than the water at the bottom. The moral of the story is to check and double check the way you've hooked up the system in a custom install because you can produce some very odd cooling characteristics if you make too many assumptions. In my case it was the assumption that two pipes that went into a manifold were connected internally to the water pump inlet, when it actually turned out that one was connected to the inlet to the water pump but the other was connected to the output of the water pump so connecting the expansion bottle to it was probably not the best idea we've ever had !

I run an aluminium rad on my 5.7, never have a problem with cooling, in fact in cool weather at cruising speed it pretty much sits at the bottom of the thermostat range. The biggest danger, which is probably worth mentioning with your history..., is that the top of the radiator is exposed on a Defender and on an aluminium rad it's at coolant temperature - putting your hand on an 80-90 degree C piece of metal smarts a bit. This is mine... electric fans only, they only get used when at very low speeds/stationary.

Towing electrics ?

A properly soldered joint is always lower resistance than a purely mechanical joint assuming they are both done properly. The vast majority of modern electronics use SMT which has no mechanical joint, relying solely on solder to provide electrical and mechanical joints. Crimping then soldering gives you mechanical security and the solder improves the electrical conductivity. best of both worlds. Either way, adding solder to a crimped joint is NOT going to increase the resistance of the joint !

Crimping and soldering doesn't work if you do it the wrong way around. Solder is soft and can migrate so if you solder first and then crimp the joint will eventually come loose as the solder migrates. If you crimp first then solder afterwards then the solder simply improves the electrical connection and provides resistance to corrosion in the joint. The crimp has already compressed the conductors so even if all the solder somehow fell out it would still maintain it's mechanical integrity. If you're making up winch cables I'd always crimp then solder the joint as you need the absolute minimum resistance, especially on 12v. Remember that to get 300 Amps through your winch motor you need a maximum of 0.04 ohms in the whole circuit. Normally a minimum of 10 connections, 12 if you have a winch cut off switch. To get the maximum out of an XP motor you need up to 500A and the only way you can get close to that is if your total resistance is less than 0.024 ohms.

Having tried both WB and NB setups and tuning from scratch, I've come to the conclusion that for normal use NB is fine. If you use TunerStudio and pay for the registered version you can use the live tuning with NB and get the thing tuned in very quickly. LC1 is OK when it works... it's a bit hit and miss though. I installed 4 of them a couple of years back on different vehicles with similar engines. 1 of them worked really well, gave steady, consistent results and made tuning a breeze. 2 of them gave erratic results that meant, at best, you could only guess what it was trying to tell you with the reading fluctuating constantly. The 4th (and last one I fitted) simply read wrongly all the time showing the wrong values and screwing up the tuning. So, out of the 4, 3 of them were "binned" and replaced with NB sensors that did a better job. A waste of money, time and effort and since I stopped recommending them I've not missed them. I don't see what the advantage of "data logging" is on a box that only sees a single aspect of the engine when you're hooked up to an ECU that can log everything and there is software available to not only analyse the log but to fix it for you as you drive.

Could you point me at some examples, been trying to find a cheaper deal for a while without any joy.