It depends on how hard you are spinning the blower. The goal is to keep the compressor from surging. Chances are, your current valve (I assume it is a Pro-Flo) will do the job. When we developed it, the red ProCharger valve (with the annular discharge, not the shrouded version) out flowed everything else by a considerable margin. I don't know that any other brand of valve would be much if any better if you opt for a big poppet type valve.