Jim Altman wrote:
>Consider the possibilty that our CD (Constant Depression) carbs generate
>less vacuum with less air and thus less fuel is sucked up the jet. Or
>perhaps the vacuum is the same at all altitudes as the piston will rise or
>fall to adjust the air flow to provide the right vacuum.
>
>Although I realize it was long ago, but in the early 70's I used to go from
>Minnesota to mountains annually in a 6 and never adjusted the carbs.
>
>I think the carbs function in a manner that renders altitude irrelevant.
>Flame suit on, fire when ready.
I think this is correct. I've been in a TR6 at about 6500 feet of
elevation, after ascending from about 1300 feet, and no adjustment was
necessary. I remember thinking that it would need readjusting, but then I
applied some thought to the matter and promptly came to the conclusion that
the air density (or lack thereof) is compensated for automatically by the
CD principle.
I know ZS carbs get their share of criticism, and I am aware of their
pitfalls, but even so, I think they're marvelous carbs.
Pete Chadwell
1973 TR6 (currently at 3650 feet elevation)
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