White spirit won't burn?

[Jules Richardson]

What was wrong with using explosives?

[John Williamson]

Work out the torque at the driving wheels, which will let you work out the acceleration, then compare that with the force required to decelerate the mass of the car at about ten times that accleration. For most cars, maximum acceleration is well under 1G, while the deceleration when you're snatching a stump is at least 5G. The safety margins are on the order of 100%, not 500%.

Then you must be driving a tank. The towbars on most cars are fastened to metal which is less than 1mm thick. Even my Land Rover has a chassis which is less than 3mm thick at the point of attachment, and that's reinforced for kinetic energy recovery, which is a posh name for doing to bogged down vehicles what you were doing to trees.

Still safe. I left London a decade ago. London's also big enough that you can always find a fool who'll buy anything you want to sell. ;-)

[John Williamson]

I can guess, but the worst that could happen to mine is that I'd need a replacement rear door, which is about sixty quid from the local breaker, and takes ten minutes to fit. The last rear tub I had fitted cost a couple of hundred and took half a day to fit.

[Huge]

Sadly, mine's a Disco 3 rather than a "Land Rover", per se. Still, I got a new lamp cluster off eBay for about 1/3rd of what they cost new and the dent in the 'C' pillar is still there. Fortunately the stump didn't come in through the (open) tailgate and hit me...

[Lieutenant Scott]

Well the tow bar is still on the car.

I'm thinking of the steel tubes which run from the towbar itself to the chassis, they're pretty thick.

I can't believe those are fastened to metal 1mm thick, that would bend with the weight of the towbar, and definitely if you for example stood on the towbar, which simply doesn't happen.

It had LPG conversion. Don't. Petrol engines were not designed to use LPG, and shouldn't be made to do so.

[John Williamson]

So you got away with it this time. You've still stressed the structure well beyond its design limits, and this may cause problems later.

They're fastened to 1mm thick metal, which is why most towbar installation kits come with load spreading plates or are designed to attach to specified load bearing points on the car. If they're tubes, then the walls will be 2 or 3mm thick, generally. If you're lucky, it'll be drawn tube, otherwise it'll be flat plate rolled into a cylinder and the edges butt welded.

It's not a flat sheet, it's shaped for strength, often into a box section, and if you don't believe me, go and have a close look at your car's structure somewhere like a scrapyard, where all the bits are visible. The bits where the bolts go through the bodywork are often doubled or have captive nuts welded to the inside, so may look thicker than 1mm, but the doubling is only for a few square centimetres.

I've worked on many cars over the last 40 years or so, and I've yet to see any metal thicker than 1/16" anywhere on the bodywork or chassis on a normal saloon or estate without a seperate chassis. I've seen some

1/8" thick metal on a Land Rover chassis, but even lorry chassis are only made of 3 or 4 mm plate, formed to shape for strength.

LPG conversions of petrol engines that can run on unleaded petrol are not uncommon, and are usually as reliable as the same engines run on petrol. Ask your local taxi firms if you want confirmation. If you're referring to the 30 to 50% increase in fuel consumption, that is inevitable due to the lower available energy per litre of LPG compared to petrol. They're still cheaper to run than petrol engines, though, as LPG is cheaper than petrol. They're not quite as cheap as diesel to run, but they're often cheaper to buy and convert.

[Lieutenant Scott]

Getting hold of the explosives.

[Lieutenant Scott]

So all those "shaped for strength" things make it strong enough. As evidenced by me getting 10 stumps out without losing a towbar.

The problem I had was the higher burning temperature of LPG wore out the valve seats (or something like that). The fitter warned me about it and said it would be ok if I used "Valve Saver" fluid. But the mechanism that fed the stuff in wasn't too reliable, so I think that may have worn the engine out. The engine eventually sounded like it was running on 3 cylinders. A Range Rover I bought already converted also sounded the same (it sounded like it was firing on 6 out of the 8 cylinders), and eventually wouldn't start at all.

[brass monkey]

Hey, that's your funniest line, keep it up.

[Lieutenant Scott]

What was funny about it?

[brass monkey]

Never mind.

[Lieutenant Scott]

I shall continue to assume you don't know what the f*ck you're talking about.

[brass monkey]

I'm sure we'll all do the same. Hey, hows about dragging the plonker into uk.rec.driving i'm sure you could learn a lot about trolling.

[Lieutenant Scott]

You'll assume you don't know what you're talking about? Ah well at least you admit it. Next step, seek help.

"The plonker"?

[brass monkey]

You know, of course you do, rodney the plonker. Y'see, you only ask stupid questions (make stupid comments). Plonker provides stupid answers, far funnier. You could learn a lot, hey, maybe get another degree. You might then make a few quid for when your VW dies in the kerb.

[Lieutenant Scott]

My VW is 14 years old. I'd say it was pretty reliable.

[brass monkey]

While you're "at it", why not go to the optician, you have selective vision, could be nasty. You can't be too careful with these things. You ask plonker, he'll tell'ya. I'll bet he's been blind on numerous occasions.

[Lieutenant Scott]

How could impaired vision cause me to think a broken car is working?

[brass monkey]

From a lad with your limited intelligence it sounds quite reasonable.

36 eh???????? hmmmmm.

[Lieutenant Scott]

The car moves when I press the accelerator. That's all I need to know.

Grow up.