I am the original owner of a 1984 Mazda RX-7 GS. The factory a/c worked fine with the original R12A refrigerant, but will not hold a charge with R134A. My mechanic says the cooling system is probably inadequate for R134A. Too much pressure builds up and a valve dumps the R134A before the a/c system sustains damage.
There are several alternates to R134A on the net, but my mechanic is not familiar with them, so is reluctant to try one. Has anyone had success recharging a 1st gen RX-7 a/c system? Are there any aftermarket parts available to increase cooling capacity?