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Subject: Air conditioning question, more

Mike Arman wrote (snipped)
>Talk to me about the "efficient scroll compressors" used on newer cars . .
>what's the deal on them? What cars are they used on? How much adaptation
>would be needed beyond brackets and bolts? If I could even out the power
>draw (smooth the pulses), I'd probably find a way to live with the rubber
>flex hoses.

>I do want my a/c to work, but don't want to destroy the drivability of the
As I recall, Audi changed the a/c system slightly for later cars; I think 
with the change to the new-interior 200 from the pre-'89 5000 models.  They 
used a relay/controller to slightly delay engaging the compressor clutch, 
allowing the engine rpm to be slightly raised (more air, probably), to 
eliminate the "stumble".  Is the drag by your compressor really that bad?  Is 
this on a turbo or a normally-aspirated car (the turbo shouldn't feel the 
drag so much; figure 5 hp drag gives 5/160 is 3%; versus 5/130hp almost 4%, 
better yet, 5/217 in my car at a 2.3%; I'd double the above percentage 
numbers, as you've likely got less than 1/2 peak hp available most times, but 
the same 5hp a/c draw...unless you normally drive flat out, uphill, near 
redline/hp peak?, full A/C).

How about an underdrive pulley for the A/C? You'd lose some of the (marginal) 
cooling capacity, and likely cycle the compressor more often, but at less 
continuous drag...