I have been using the standard pump with 20 idle and 55 anything over 1,800 rpm that is hot with 10/30 VR1. If your egine was set up " tight" go standard if loose high vol.
x2. I tend to build tighter clearances and run std pumps with the high pressure relief spring added. My engines are around 20psi at idle and 65psi peak with 10-30 oil at operating temp. Unless the clearances get bigger or there is sustained high rpms, you don't need high volume, and it does cost power and generate more heat.