My fuel pressure is at 50 psi then when I hit boost, it goes down to 35 psi. From what I heard from the guys at the dyno I was at, this is not right. Is this bad?

I had my fuel pump changed by someone else a while ago and assume he put in the Holly 255 that I paid for. How can I check if it is a Holly I have. Please don't think I am stupid because I have never changed a fuel pump.