oil pressure relief valve

I got two questions that I need help with. 
First one is about the service manual for 1983 GPZ1100 where it states the oil pressure relief valve opens at 63 - 85 psi.  
Can this be true with the normal pressure for this bike runs from 0 to 15 depending on the oil temp and RPM of the motor? 



 
The second question will it matter if I run an oil pump without a relief valve on my 1983 GPZ1100? 
I am installing a gate on the oil pan baffle and the relief valve is in the way. 




Thanks in advance for any help you can give me.