The evap unit (under dash) needs to have an expansion valve setting that matches the freon type in order to be optimum. That's the "design" issue of new vs. old AC systems. The other part of course is that 30 - 50 year old A/C systems are usually worn, dirty, etc and need a big overhaul. Condenser fins bent, plugged with dirt, etc. Also factories got cheap with condenser size (more is always better here!) in some years. I had h134a in a 75 gremlin with a factory evap and condenser, new Sanden compressor -- in Tucson AZ. Now if you want car AC done right go to Arizona!!! It worked GREAT and would freeze you in 100 degree F weather. System was flushed and had some new hoses. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://list.amc-list.com/pipermail/amc-list-amc-list.com/attachments/20100408/28bf6b3b/attachment.htm> _______________________________________________ AMC-list mailing list AMC-list@xxxxxxxxxxxx http://list.amc-list.com/listinfo.cgi/amc-list-amc-list.com