For all:
Sunday afternoons I have taken to hanging out with a guy in the
neighborhood who has several MGs. He bought a color tune and
wanted to know how it worked (great guy, not very mechanically
inclined). Well, we tried it out on the Datsun. Its basically a
generic spark plug with a glass window. When you start the
car you can see the color of the flame taking place in
the combustion chamber. I did the forward cylinder and the
aft cylinder. Both burned with a Bunsen burner blue flame
which is supposed to be exactly right. Interesting that when
you blip the engine, you get a moment of yellow flame, indicating
a rich mixture on acceleration, just what a well adjusted SU
is supposed to do. When you suddenly close the throttle you
get some yellow flame for a second or so also. This would seem
to me to be the hydrocarbon rich air polluting phase that the
air pump was supposed to help do away with on the 68-70 cars.
Bottom line, if your car is running great, no need for this thing,
but if you can borrow one while tuning carbs, it could be
a useful tool. BTW, my spark plugs are a very dark tan,
indicating a mixture just on the rich side of exactly right,
which agrees closely with the color tune.
Best Regards,
Jim
Chesapeake Va
67 pushrod 2L 5spd
72 510 sportwagonGet more from the Web. FREE MSN Explorer download :
http://explorer.msn.com
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