Good review of the subject Art. The biggest obstacle to complete
metrification in Canada of course is the US. The constant need to use two
systems - because of US-Canada trade has been one of the greatest burdens
on our economy. One of the most frustrating things for mechanics has been
metric hybrid cars which were produced starting about 1977 where many of
the fasteners were metric in a car which was largely inch measure.
On the TR7 the engine and many associated parts use metric sizes thus it is
somewhat like most American cars of the late '70s - early '80s where the
mechanic must take two sets of wrenches to work on the car. Particularly
frustrating was the choice of some sizes on GM cars of that era where
uncommon metric sizes - such as 18mm - were used on fasteners which
required regular attention, such as adjusting bolts for engine belts.
Check the average package set of metric wrenches or sockets. Notice which
sizes are not regularly a part of the set. GM chose those.
BTW, my Standard Vanguard uses all SAE fasteners which is as you have
stated correct. The Vanguard, introduced in 1948, was the first
Standard-Triumph vehicle to do so. It was also the first LBC to use a
nearly square bore/stroke ratio.
John McEwen
>In a message dated 98-01-03 18:04:23 EST, curry@wolfenet.com writes:
>
>[in reply to John's e-mail:]
>
>>> In Canada however, their are two systems:
>>> metric and SAE.
>>> I assume that the US is the same.
>
>> John,I use good ole' USA standard "inch measurement" tools on my Spit
>_______________________________________________________________
>
>Joe et. al. Those "good ole' USA standard 'inch measurements" are the same as
>those measurements called SAE (for the Society of Automotive Engineers). The
>SAE is a U.S. (and maybe Brit/Canadian) organization which adopted those
>measurements commonly in use at the time of the adoption. The standard for
>length was yards and - from yards - feet and inches. In addition to the
>standard for length, the SAE adopted standards for lubricants and other
>automotive parts.
>
>Yards, feet and inches were originally English Measurements. We use them in
>the U.S. because we were British colonies. The U.S. first standardized ALL
>U.S. measurements in 1830 and made some changes - that is why the U.S. gallon
>is different from the Imperial (read Brit) gallon. But linear measurements
>(feet, yards and miles) remained the same in the U.S. as in the U.K. from
>colonial times to the 1970's when the UK mandated the metric system as the
>standard.
>
>Our TR's were built in the 1950's and 1960's using the English System of
>Common Measurements. The standards for length are the same as the SAE
>standard of measurements for length. U.S. car makers in the '50's and 60's
>time frame used the same system of measurements. U.S. car makers are
>currently moving toward the Metric system as a standard and have been for
>about 20 years.
>
>To add to the confusion regarding British built cars, the Whitworth standard
>of measurement was another British system used by Brit car makers. This
>system was originally designed for fasteners (screws and such). The Whitworth
>system was in inches but used a different way of measuring bolt heads. This
>system was in use in U.K. industry (not the U.S.) from the mid 1800's until
>the mid or late 1940's. British auto makers used the British Standard
>Whitworth during that period, which is why early Brit cars need "Whitworth"
>wrenches. (Moss and others still sell them). By the time our Triumphs were
>built the Whitworth system had been abandoned - 1944 actually. Some Brit auto
>makers used the Witworth system into the 50's and maybe the '60's but Standard
>Triumph did NOT use it for cars designed/made in the 50's and later. But that
>is a whole other subject.
>
>France developed and standardized on the Metric System during the Napoleonic
>era (1801) and by 1900 the rest of continental Europe had followed suit. The
>Brits remained on the "British System," that is yards, feet, and inches until
>the 1970's when they finally mandated a move to the Metric system.
>Interestingly enough, in 1893, the U.S. defined the yard based on a metric
>equivalent! By the mid-20th Century the U.S. had recognized the metric system
>for legal use in the U.S. but not as the standard for our measurements. U.S.
>automakers started a transition to metric measurements during the late 1960's
>in order to better compete in the world marketplace. That is why, as someone
>on the list pointed out, some U.S. cars today have some metric components.
>
>It appears to me that we unnecessarily complicate this whole subject as
>regards our cars. When our TR's were being built, the U.S., and the U.K. and
>its other/former colonies (Australia, Canada, NZ, S.A. etc.) were all using
>the same system of measurements. That system is what we call Standard or
>S.A.E. here in the U.S. It is what was used in building our Triumphs because
>it is the same system which the Brits had invented and used for centuries and
>what they went back to after abandoning the Whitworth system. As for Triumphs
>built in the '70's (for example - the TR7's and 8's) - Since the U.K.
>converted to metric in the 1970's and remembering that you can't convert
>overnight because of the amount invested in existing machinery - I'll guess
>that some fittings were metric on late Triumphs.
>
>BTW - in the '60's I always had mechanics trying to use metric wrenches on my
>TR4 because it was a "foreign car". In those days, as now, German, French,
>Italian, Japanese (not very many around then), and Swedish cars were metric.
>I found that the best thing for me to do was to assure the mechanic that the
>Brits built their cars to our specs. This was not really true but it wasn't
>false since the specs were the same.
>
>As an aside - 95% of the world now uses the metric system but reactionaries
>in the U.S. keep blocking our complete move to it. We spend years as kids
>learning fractions just so we can deal with the "English System" which is
>defined as the "United States Customary (from Custom house) System." The
>Metric System requires no skill with fractions. IMO, it is pretty dumb to
>have to constantly make calculations such as "what size wrench is between a
>3/16th and a 5/16th" (it's a1/4 in) or that a 1/2" wrench is between a 7/16
>and a 9/16. With the metric system all one needs to know is that 6mm comes
>between 5mm and 7mm. If we in the U.S. mandated and moved to the metric
>system it would take about 40 years (2 generations) to be completely rid of
>the old inches/feet based system. The way we are now doing it now will take
>about a hundred years or more.
>
>But I digress. The answer to the original post is that when working on your
>Triumph you will need tools called SAE or Standard if you live in the U.S. or
>Canada. However, you might need some metric wrenches or sockets if your
>Triumph was built during the '70's or if the DPO replaced nuts/bolts or parts
>and incorrectly used metric replacements.
>
>This is not the definitive story of these measurements. There have been books
>written on this. I have merely tried to cut through a little of the
>confusion. AND I await the inevitable corrections/expansions. Cheers.
>
>Art Kelly
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