Sorry for the lack of input conditions. I have converted to r134 five years ago and have recharged. my current input pressure to the compressor after recharging in running norm is 40 psi. the cold air output has improved, but I am checking on if the 40 psi input to the compressor is ok.
40 psi is in the "good" range, but there are conditions that could cause the system to not work well anyway, such as a partially clogged orifice tube, or contaminants in the system. If you have an AC manifold set, check your high side pressure also.