I searched in the archives and online in several places. Starting with a Vacuumed down system, how much 134a is spec'd in this RX ?

 

80% of the R-12 charge is a good starting point....then adjust up or down depending on pressures and performance. Should be a sticker under the hood indicating what the R-12 charge should be. BTW, R-134a will give you lousy performance.

 

You will be even more confused when you have shitty A/C in Schreveport! Use Freeze12 instead-Ebay and use about 80-85% by weight of the original spec R12 charge.