Saturday, Nov 06, 2004 at 19:10
One of the big problems with this sort of stuff are magazine reports that are presented as 'tests'.
There are rare exceptions (like Alan Whiting, the now sadly deceased writer Brian Woodward, and myself) but the vast majority of writers in this field are journalists who have no engineering training or background. We (or at least me) on the other hand will never be able to compete with Roothy as a truly entertaining writer.
They are thus (with things like fuel 'savers') primarily reporting an interview with an interested vendor with a considerable vested interest in a good outcome. The journo may
well supervise the
test and be sent off with a 'test car' - but such tests lack virtually credibility not least in methodology.
Journos do a good job over a wide range of stuff, but are frequently way out of their depth in areas like this.
As I noted earlier on this thread, it really is surprisingly difficult to measure fuel consumption accurately - so just consider this also:
In an article (on a fuel 'saver') the journo reported a fuel consumption saving of (something like) 1.06 litre/100 km measured over 200 km. That's 2.03 litres of fuel. It was shown to those two decimal
places and that second decimal point implies an accuracy of 0.01 litre - that's a bit less than one tablespoon full.
The journo reported this was measured by filling the tank to the brim in a vehicle with a plus 100-litre tank. Come on!!!!!!!!!!!!!!
That result is way within experimental error. Do it again tomorrow and you'll get a quite different result. And the next day - and the next ....
Re naming vehicles where these trhings may work - it's mostly vehicles with carbies made made prior to the mid 1970s. The 1930-1970 was the era of these things - and there were zillions on the market.
Look at this way. People like me who actually designed and developed motor vehicles cannot ALL be total idiots. If these devices lived up to their general claims does anyone seriously believe we were/are all to b-y stupid not to utilise the technology.
If one could gain even 2% in efficiency and power output, without prejudicing any other characteristic, one could obtain a Ph.D virtually for the asking - and probably make a fortune as
well!
Collyn Rivers
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