OK, I got plenty of responses on this one but in short, It appears the aircon can use up to 25 horses from the motor and repairs on most C3 models area apparently quite epensive.
Here's a couple of responses from the US ....
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The antique Compressors do take away some poewr and economy, and 1.5 MPG on my
406/375 71 Coupe at cruise, though I don't have any track times with the AC
on...(:>)
Doug
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They do rob a lot of power, but in most of the cases, at least up here in
New England, the a/c is just not that important in that type of car. Also,
your feet are on fire, especially big blocks, air or no air. Regards, Ray
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What's and AIRCON????? I owned a C3 for 11 years. I don't remember having an
AIRCON, but if I did have one it was always connected.....I think because I
don't know what an AIRCON is!!!
RED ROCKET 92LT1
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You can feel it with 375 - 400 HP, though, I turn it off if racing...(:>)
The old compressors take a lot more HP to turn than the modern one's do, and
they don't cycle. There's supposedly a new POA Valve or some such gizmo that
you can upgrade to get cycling, which should help your MPG a lot (50%?).
Doug
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There's more but yo uget the drift ...
Thanx for your responses guys ...