ColorTune and such . .

[Chris <chris@domain.elided>]

In response to Frank Formeister's message regarding tuning with CT, my
two cents. (CT is ColorTune, of course)


I tried CT on a Triumph Spitfire mkIII once, worked very well! Mind you
this is a 1300cc car with dual SU carburettors. And calculates to one
carb per two cilinders.

Then I thought: "Hey, let's try this on my Alfetta."
It's a 2.0L with dual Dell'orto's . . . one-carb-per-cilinder.
Made sure the carbs were statically correct, all "flaps" openend at the
same time. With CT I always got yellow (rich) readings, whether I turned
the adjusting screws 1/4, 1/2 a full or even two turns from the "basic"
adjustment (which is 3.5 360degrees turns from stop). Might be because
the Dell'orto carbs are "naturally rich", or my engine is old (oil
burning) I tried with and without air filter, even withouth the
airfilter
box as to reduce/eliminate car-to-carb influences.
Then I reread the CT instructions, and they said: "Use [on such equipped
engines] _FOUR_ CT-plugs"..Hah! No way! That's is marketing speak!

So ,IMHO, CT is best used with single or dual carb'ed, engines.
(dual carbed as in: one carb per 2 cilinders) Then it works well.

On new or rebuild engines I think it's justified to pay the "odd" $200
for letting it have tuned professionaly.

If you _WANT_ to DIY, get 4 vacuum meters and adjust your carbs 'till
all four show the same "suxion" then drive to a garage which has CO%
measuring equipment. Adjust until mmHg (vacuum) is the same in all four
carbs and CO is about 3%(if there are 4 mixture adjustment screws. If
there are only 2, it should be 1.5%).
Then at the next emission test repeat above until .5% CO, if passed test
reset to original  :)

Alternativley, find an old Weber-bloke, he adjusts your carbs just by
listening, I've seen it done! remarkable feat . . .

Sincererly,
    Chris Piepers
    The Netherlands

"I know my english isn't that good, but if I spoke my native language,
you probably wouldn't understand me at all :))"

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