Turbocharger

WSM has a car park which allows access but I'd advise against driving anywhere too fast there.

Paul - give the lad a break. He's bashing out a degree at the same time - there's drinking to be done. I had enough on my plate studying and keeping my Ninety running through Uni.

Diesel – Calorific value 42.5 MJ/kg. Ideal AFR 14.5. Density 840kg/m3. Petrol 98RON – Calorific value 43.5 MJ/kg. Ideal AFR 14.7. Density 750mg/m3. Ethanol – Calorific value 26.8 MJ/kg. Ideal AFR 9. Density 790kg/m3. LPG – Calorific value 26 MJ/kg. Ideal AFR 15.6. Density 540kg/m3.

It's impossible to tell what was in the tank from a 'he says X but they say Y' account. Take a fuel sample and prove it either way? If it's a full tank they won't miss a cupful. If they've drained the tank to determine the damage, ask for a sample of the drained fuel (and if they've disposed of it, ask how).

I've just put a V8 ZF box behind a 300Tdi, with mixed results. The setup now works well, the shift points are fine for a Tdi and it kicks down when asked, it works well on the road and has all the expected benefits of a torque converter offroad. In low range the shifts are harsh but it does everything it says on the tin and the engine braking is not too bad too. The only limit is on top-end speed: if you're on the motorway at 80mph and want to go faster, you put your foot down and it shifts to third which is "exciting" for the little diesel beetling away up front. Overall I'm very pleased with it, perhaps a little thrashy but I'm planning a higher-ratio t-box to help that. Installing it was rather harder though. You need a converter ring to mate the bellhousing to the Tdi flywheel housing and it should come with a solution to bolt up the innards. I've got a flywheel, flex plate and torque converter but I think the factory ones use a light-weight 'starter ring' instead of the flywheel and I've heard of solutions which bolt the t/c straight to the flywheel. Mine was harder because it was a 200Tdi kit and didn't have all the bits I need but (touch wood, fingers crossed) it's all in and working now. I'm in Bristol if you'd like to come for a look.

They might be dimensionally accurate but metallurgy is the biggest difference between a quality part and a cheap copy. I'm not saying that the cheaper ones aren't fine but a narrow harder layer might improve resistance to fade or high-temperature distortion, for example. Despite being a lifelong spendthrift, I'd spend the money.

Well, we looked at the post-NERC lanes in S Wales and they were too far for a day out so we took a gentle bimble around the south side of Bath for some gentle lanes and wildlife. I was a little confused after some friendly banter with passing horseriders while we enjoyed a brew (shouldn’t they abuse us as normal?) and saw pheasant, partridge, hare, fox too. Other than some bikes, didn’t see any other vehicles really and had a quiet few hours enjoying the countryside. Next time I’ll take the roofrack off before I leave home!

If you use a Hall effect sensor looking at a toothed wheel on the CV or hub, I'd expect it would be a square wave. Why not log it or use an oscilloscope to have a look at the signal?

I admit I used plain ally and dome-head screws, no sealant or foam but then the car was 15 years old when I installed them and not 'pristine'. Welcome Boot - I recognise a certain ford in your avatar I used to live near Ashbourne.

Can someone post a pic for those of us who hide behind an IT ebaywall?

Jim / Wikipedia is 95% there - it drops all the pressure in the manifold, turbo inertia etc so that your petrol engine doesn't go very lean (too much air) when you open the throttle in the next gear. Not an issue with a diesel (and to be quite honest, not really an issue with most road engines/gearboxes but if rally cars make a 'pish' noise, Kevin's Corsa must make a pish noise too.

I've never met Gresh either but he's been active on quite a few of the forums. Opinion seems to paint a picture of a steady sensible chap who will never get back what he has lost. Thoughts and condolences are with you after a terrible accident.

I've just put a V8 autobox behind my 300Tdi. It's quite possible but you need the right bits. I bought a conversion kit second hand on here and I thought I had the right bits but it turned out I didn't (and the bits that I had hadn't been installed quite properly) and it ate a flex plate in short measure. With the right bits it's just a nut and bolt job. The hardest bits to find are a conversion ring to mate up the bellhousing to the flywheel housing, and 'some method' of bolting the torque converter to the crankshaft. I'm using a manual flywheel with some holes tapped in it to carry a spacer and then the flex plate, but its a very heavy option. It might be rebuildable with the correct auto starter ring (much less inertia) but it's together and it works so it can stay for now! All seems to be running ok now, offroad it's a boon and on-road it's nice, although the fuel economy has definately taken a hit. Starting again I'd do the same, but if I didn't have the right bits (a Tdi auto kit would be easiest) I'd seriously look at a manual.

Mornington Crescent! (Is this thread done yet?)

Tractors sometimes run water in the tyres for extra weight (or mass) - could they get extra performance from knowledge partnering with the nuclear industry and use heavy water for even more traction? Although you're my Dad you can't pull the "blood's thicker than water" card. I'll trade you an associate membership of the IMechE and a 25-metre swimming certificate for your FRGS, six quarts of (uncompressed) Exmoor air and a digestive biscuit. Final offer or it's all going on Ebay.

No no, a lighter tyre radiates less heat, an easy confusion to make. You can borrow my MEng for as long as you need it, but if you want the (Hons) too I'll swap for a boggo tyre gauge and a speedo calibrated in furlong/fortnights (with conversion chart in original condition). Jez - obviously there's no hard rule to decide if you rotate the tins clockwise or anti-clockwise, it depends how they were filled (although interim stirring can confuse this). There are a number of rumours about this, the only way to be sure just be sure to turn the tin upside down if you meet any stiff resistance to conserve the gyroscopic motion. Going off-topic (oh, NOW he's going off-topic) would I need to alter the pressure in my tyres if I filled them with helium? The mass of gas would be different but the stp volume would be the same - what is the effect on ground pressure?

^^^^ what he said. More mass of air in the same volume of tyre = higher pressure. I concede it is a fact that this high-pressure air would occupy a larger volume at room temperature & pressure but it's not helpful or useful to try it. Glaggs - if you're desperate for a formula I'd take the max load fraction approach for a starting point but on your way back from pumping your tyres up I'd buy some chalk. Otchie, if you need a BSc you can borrow my MEng for a bit until you get your own (or will swap for a calibrated tyre pressure gauge).

Jez - are you rotating the tins on the shelf to ensure even wear? I seem to remember a certain forum member making a compressor out of refrigerator parts. He was having cornering problems, his car would enter a roundabout and then refuse to leave it. After months of confusion he emptied the air out of his tyres and blew them back up again on a petrol station forecourt - it turned out that the fridge compressors were making left-hand rotational air, when everyone knows that car tyres need right hand (clockwise) spinning air. That's why Jaguar moved away from left-hand-thread wheel nuts holding the nearside wheels on on their pre-war cars - same problem. Apparently you can completely balance out the handling of your car with a old clockwork compressor and racers on the Nurburgring will see better lap times with this technique - this doesn't spin left or right, and is known as 'wind up air'.

No, the pressure of the tyre affects the running temperature, since a lower pressure gives a larger footprint, so the tyre deforms more as it rotates, absorbing more energy which heats the carcass up. You could argue that the additional air mass will alter the rate at which the tyre changes temperature, but since air has a relatively low specific heat capacity the volume of rubber will dominate the thermal inertia of the assembly, and in any case the large surface area and copious cooling (external) air will negate the effect of an extra 10% of air (by mass) in the tyre.

If it's been used, don't breathe it. Breathing high-entropy air is a major cause of death in crowded confined spaces such as third world jails. In Ethiopia up to 75% of deaths in non-confinement jails are wrongly attributed to another cause because of ignorance. It's heart-breaking. As you may have guessed, most of what I'm writing here is dross, aiming to show that you can prove anything with a few numbers. Quick answer: You need a force to hold your car off the road. It's air the in the tyre that provides this force, using pressure. (Ignoring the sidewall stiffness for now). The force to hold your car up is constant because the weight is constant. Force = pressure x area With a low pressure you need a larger area to provide this force. Nature intervenes here and the tyre takes a 'flatter' shape so the footprint 'area' is larger. However, once the tyre is a flatter shape it's also wobblier and harder to control from above, so the aim is to balance the two effects. 20-30psi is usually about right, unless you're aiming for mega MPG, offroad or your name is 'Jez'. The chalk method makes sure that the tyre is pressing down the same all the way across, so that it'll wear evenly.

To answer the question, you have to go back to the fundamental laws of thermodynamics from Boyle, Hooke and their French cousin, Carnot. The laws of thermodynamics state "you have what you have", "you can't get more than you've got" and "you can't actually break even". The First law says that you have a certain amount of energy contained in a system (the pressure in the air) and this cannot increase without energy being added, usually from a compressor. The pressure in the tyre cannot decrease without an energy transfer, but since heat energy can be exchanged with pressure energy (and indeed the balance of these products is defined by the adiabatic, isothermal or other type of compression) the pressure in your tyres will change on hot or cold days. You could inflate your tyres by trapping a volume of air in them and then heating them (closed system) but they will deflate again when they cool. This same process means that the volume of trapped air does not change but the pressure will do so after repeated heating/cooling cycles mean that heat energy is lost from the closed system each time; the air 'fatigues' in the same way that metal sometimes does. This is why you will sometimes see cars or lorries stopped at the side of the motorway with a flat tyre. This can be combatted by checking your tyre pressures regularly and adding more air to compensate for the low-entropy air that is currently in the tyre if the pressure is low. Scientists at Michelin and Dunlop increasingly recommend emptying all the air out of your tyres and replacing it every three years, allowing the entropic heat loss process to start again. The Michelin test facility in Dusseldorf is building a library of low-entropy air (collected in low pressure glass receivers) and they are experimenting on this air to show the effects of thousands of stop-start cycles. Energy can also be mechanically added or subtracted from this closed system. A large force applied over a small distance will give 'work done', which is a transmission of energy. This effect means that the weight of your car will push the bottom of the tyre inwards slightly, increasing the pressure of the inflated tyre. For this reason, the best mechanics at Rolls Royce and Bentley garages use air pressure gauges which are calibrated to check the tyre pressure with the wheel in the air, and old-school RAC mechanics will jack up your car before they check the pressures. Anybody else is taking a shortcut, or simply a poorly-educated cowboy. Time for the chalk I think.

What kind of temperatures do autoboxes run? Could I mount another water temp sender and wire it through a switch to my water temp gauge (which is marked in deg C)? Obviously the red bit wouldn't be applicable but it would give an idea?

First - assess if you need a car. If you're working within the Tube or bus network, you don't really although it may take you a little longer to get to work. www.tfl.gov.uk has a journey planner to let you know how long it'll take - it's uncannily accurate. First Great Western will take you from Plymouth to London for a reasonable fee if you book in advance. I'm afraid Plym is too far for me to drive down and give a hand, but hopefully that will buy you some time to pull the engine out and do the seal at your leisure. Then work out if your newly converted steed is compatible with the London Low Emission Zone, or else you might be leaving it down in Cornwall anyway. Well done on your new job though!

I've not had a fan on mine for nearly two years now. No issues except when offroading in hot, sticky, still woods, or sitting on the motorway queuing after working the engine hard. When a diesel isn't working, it's not making heat, you've just got to spill the excess that you made before you came to a stop which is why it gets hot sat still on the motorway. I'd say you'll be fine in the UK with an electric fan.

Well, this one's a backstop so next door's cattle don't get too shot, but he also has a stone Bickhenge patio area which aligns with sunrise on the equinox or somesuch.