Snakey wrote:

That's a spot on assessment in my view. Regular changing of spark plugs
benefits only one category of person - those who make them if you need
explanation.


Well they do eventually degrade..its actually cheaper to replace them
than to actually clean and regap them, and its a LOT cheaper to change
them once a year than get non starting car towed home or to a garage.

In 40 odd years of motoring I have only had to change a few plugs for really
identifiable reasons i.e. the electrode was starting to disappear into the
insulator through erosion and part of the insulator cracking off and
detaching itself causing a misfire.

Bomber Command used to have a "spark plug " crew attached to every squadron,
whose duty was to clean, gap, test and stuff 'em back into the aircraft. I
think you'll agree that was a fairly critical application?

Less so with 4 engines each with 12 cylinders and (not sure, 2 plugs per
cylinder?)

As for the copper tip/ iridium tip BS, that's just marketing crap of the
highest order and deserves consigning to the same category as those
misinformed persons who think that paying £30 for a can of oil for their
pride and joy will make it last forever, or even make it last ANY longer.
Someday the connection between "longlife" oils and the appearance of "engine
sludging" problems may be made in the minds of the hard of thinking.


Well again, yes and no. Under certain conditions certain plugs will run
better than others ..if you are in the business of screwing the last
horsepower or mile per gallon out of an engine, the plugs are certainly
worth swapping around to see if a particular type works best.

Read one particular chapter of Ernest K Ganns book 'Fate is the Hunter'
for a truly terrifying tale of 'new spark plugs' in a set of engines on
an airliner.."we didn't have time to change them on the last engine,
sir" " and thank christ for that..it was the only one that ran reliably
over 3000 feet altitude"

Al spark plugs are not created equal, and they are an integral part of
engine operation.

That doesn't of course mean that Super Unobtanium Plasmaplugs are
anything more than a load of hyped up ******** of course..just that
there is some potential for them not to be.


Snakey