I'm sure that you change your oil regularly so this probably won't help you but I thought I'd share. I've seen some people who constantly run their vehicles with the oil being low and showing low pressure. Whenever it is under acceleration the pressure will rise. Like I said this probably isn't the problem but I thought I'd throw it out there.
What are you trying to convey
All vehicle's oil pressure rises in relation to rpm. The oil pump is driven by the distributor or opda depending on year. Both are connected to the cam via gear mesh. In newer vehicles the oil pressure gauge is a dummy gauge and doesnt show true pressure, just high and low.