When its 70 F My AC runs nice and cold, over 80 not so much. SO I shoud be abl et o run it over to a AC shop for some more R12?

 

Curt,
No problem getting R12 just what a shop may charge you for it. Could be $90/can.
Ask before you commit.
Roger

 

Stick to R-12, there are plenty of independent shops around that still have it and it has been my experience that 928 systems work much better with it. 134 is no bargain these days anyway. Fix yours and stay with R-12.

 

Since the earlier cars came with R12, and the later ones with R-134, what are the differences in the systems that Porsche made between them? If a car came equipped with the R-12, what all would need to be changed to covert it's A/C system to be the same as the ones Porsche installed on the later R-134 cars?

 

My educated guess would be compressor, condenser and expansion valve. Maybe also the evaporator.
A check of part numbers in PET would pin it down.

 

There is no drop-in replacement.
Re Duracool. Ask yourself if you want a flammable gas in there? Under pressure? Mounted low and up front so as to be one of the first things to take impact in the front end or from bottoming. Most of the cheap so-called replacements are butane or propane derivatives. I would not.

 

I had a bad hose about 5 years ago, and w/all the hoopla surrounding R12 in CA, I converted to 134. had to change the dryer and some old seals - then refilled w/134 and it's been cold as ice w/my dual AC system in 100F+ socal days w/no problem, even idling in traffic.

did have some contacts get nasty on the low pressure switch last month, but after they were cleaned up life was cool again

 

Ditto.. I have 134 and it will blow you out of the car even at low settings on a very hot day.