Best AC compressor to buy

[Lincolnmania]

i am only going to use motorcraft remans from now on........the new ones are crap and the other brand remans do not seem to hold up.........the price from ford is not much higher than a new made in china compressor.

[tjc78]

h8 you R12 people. Mine gets down to 40-42 driving, and goes up to nearly 60 at a stop. Stupid enviro-friendly nonsense refrigerant.

I never tested the output temperature, but I don't remember my 134 converted 89 LTC getting that much warmer at a stop. There was a bit of difference but nothing drastic.

[gadget73]

Underdrive pullies do not make for good idle speed AC performance. Its not just the R134, at least some of it is the pullies. Less airflow plus less compressor action really makes it suck. It would go up with R12 under those conditions too, though probably not quite so much. I'm gonna try fitting a pusher fan to see if I can get some improvement from it, and I'm also going to look at later model native R134a cars to see if their more efficient condensors can be easily retrofitted into my car.

[alchemist]

I've always liked Seltec-Valeo compressors, especially the HT6 knock-offs that they make. Quality seals internal.

[drhill]

R12 is out there...I was amazed how much of it popped up on craigslist during a few weeks of searching...I struggled with 134a conversions for the last couple of years...r12 condensers are too small, 134a does not keep vent temps at idle as well...for example I dropped my vent thermometer into a brand new 2012 buick we have as a company vehicle...of course 134a but designed for it...vent temps never got below low 40"s (i imagine by design) and sitting at a light, right at 50 degrees. Brand new car, electric fans etc....it was over 100 outside but my wagon has no problem getting down to 37 or so at 110 degrees outside...44 or so at stoplights.

For a 134a conversion, gadget's numbers seem pretty good to me depending on the ambient temps...

[sly]

yeah... best bets are to swap out the condenser as well when doing the 134a conversion... but that's a PITA on most vehicles.

[alchemist]

R12 is out there...I was amazed how much of it popped up on craigslist during a few weeks of searching...I struggled with 134a conversions for the last couple of years...r12 condensers are too small, 134a does not keep vent temps at idle as well...for example I dropped my vent thermometer into a brand new 2012 buick we have as a company vehicle...of course 134a but designed for it...vent temps never got below low 40"s (i imagine by design) and sitting at a light, right at 50 degrees. Brand new car, electric fans etc....it was over 100 outside but my wagon has no problem getting down to 37 or so at 110 degrees outside...44 or so at stoplights.

For a 134a conversion, gadget's numbers seem pretty good to me depending on the ambient temps...

134a has very similar thermal properties to R12. R12 has a lower boiling point (-22F versus -15F for 134a), so the evaporative cooling by 12 going from liquid to gas is going to provide more delta H. (positive = endothermic). 134a has the 'environmental' advantage of having no chlorines in its chemical structure (it's all fluorine); however, it is not quite as friendly to metals and synthetics as R12. 134a requires a more hydrophilic lubrication oil, which pulls in water. Any water in the system will also compromise the performance of 134a. I worked on 134a back in the early 90's in the medical field when it was replacing r12 in the metered dose inhalers (e.g. albuterol). 3M and Dupont worked together with my professor when I was a grad student. It was one of my side projects (or more aptly called, "side show projects"). We proved that rats, when exposed to the 134a gas, metabolize it entirely through their lungs unchanged. We were unable to detect the 134a in their blood; albeit we were at limit of detection.