Evidence Based Arguments - Was: <gloom>

Mother"

On Thu, 09 Feb 2006 19:01:55 +0000, Mother scribbled the following nonsense:

sounds fun, during the week is out, but weekends sound good.

As a slightly related issue, I'd like to see evidence pro or con my opinion that running an old car 'forever' is better (in terms of total pollution/waste created) than someone who keeps buying new cars.

I'm running a 25 year old saloon as a daily driver currently on LPG, but the same thing/argument could be said of many landrover drivers..

Mother"

Well don't look at me, I only get through an MOT on emissions because of age and luck

On that tree-hugger website posted in another thread recently (memory fades) it was reckoned that making a car produces just under two thirds of the pollution the car is ever likely to produce throughout its life, with one third being driving emissions and the remaining smidgen being the cost of trashing it. There were references in the article to studies that might be worth you following up.

Now if only I could remember the article URL ;-)

I think you need to be _very_ sure of your science, or it could backfire on you (like an lpg Rangey).

MoT machines measure percentages, not totals. To a first order guess, exhaust volumes are proportional to fuel use (mpg, litres/hour, cubic furlongs/fortnight); if a certain large purple machine achieves 12mpg, and a small petrol car 36mpg over the same journey, then you'd need to achieve under a third of the "MoT" emissions to even partially prove your point, and, with all due respect to large, purple etc, I doubt if you'll achieve that.

But "MoT" emissions are only part of the story; some green people are worried about CO2, and the total quantity of this is almost entirely a function of total fuel burnt - so you're in trouble again.

Don't get me wrong: I'm all in favour of appropriate use of 4x4s and other large cars - with a Range Rover and a Bentley out there I could hardly say anything else, but I wouldn't claim they're "low emission". Anyway, a propos of CO2, I'm a great believer in Le Chatelier's principle (anyone else remember their A-level chemistry?)

"If, to a system in equilibrium, a constraint be applied, a change will take place which tends to nullify that constraint". So if there's more CO2, trees and other plants will grow faster to take it up.

On or around Thu, 9 Feb 2006 22:12:21 -0000, "Nige" enlightened us thusly:

Bring the WRX, I bet that kicks out some heavy CO2 if you boot it.

They're s'posed to test the car, Larry... :-)

On or around Fri, 10 Feb 2006 08:32:59 -0000, "Autolycus" enlightened us thusly:

then again, the large purple etc. probably only burns a smallish amount of fuel due to the amount it gets used.

I see there are new plans for cunning coal fired power stations which don't belch out CO2. Mind, that doesn't address the use of fossil fuels, but it does prevent them adding to the CO2 burden. What you really need is a use for CO2. Making heavy baloons, that hang downwards, perhaps.

I think you might be best forgetting about this train of thought, as Autolycus says it's very likely to backfire. There are other ways of pointing out how 4x4s are better for the enviroment in some cases than other vehicles but everyone's situation is different... emissions at individual tailpipes is inviting mockery as they are going to be relatively poor compared to most other vehicles, and it doesn't take into account vehicle's useage.

Are you running EFi with closed loop, wide band lambda control and a catalytic converter? If not, then I wouldn't dare to challenge anything that was relatively recent. Remember Morgan stopped using Rover 3.9 and 4.6 V8s citing EU emission legislation as the reason. Your average supermarket Toyota Yaris will be _very_ clean.

Of course, doing it in a TV report style, take a nice warm Grumble, find anything that's over 10 years old and looks like it hasn't ever been serviced, start it from cold, and take your readings to "prove" your point!

Regards

William MacLeod

It isnt the best in that terms! Wonder against the 4.6!

Nihge

--

-- Subaru WRX Range Rover LSE (Bob) FOR SALE!!! Range Rover 4.6 HSE (The Tank!)

'"I don't remember asking you a goddam thing"

On or around 10 Feb 2006 11:30:03 -0800, " snipped-for-privacy@macleod-group.com" enlightened us thusly:

I rather thought that the supply of RV8 was about to dry up. The engine, with cats and modern injection system, was no doubt as clean as any other with cats and modern injection system.

snip

They do still belch out CO2 just that they intend to capture it and pump it underground. Goodness knows where it will go then. Whatever happens lecky will still cost an arm and a leg.

Peter.

Land Rover now has an engine which has variable camshaft phasing and DOHC amongst other things, that means the computer can control its 32 valves more efficiently than the old 4.6, so with all the fiddling in the world you are not going to get the old 4.6 to be as efficient as the new 4.4. Sure you could have it tuned for similar emissions at one particular load/rpm but that doesn't mean too much, your emissions start when you start your vehicle, and end when you shut it off and I think you'd find a significant difference between a P38 and a new RR if you were to bag the emissions over a journey.

Regards

William MacLeod