I read on a site that adding a 6.25mm spacer in-between the release valve on the oil pump on a 1600 that it add 15psi more oil pressure? Is this true and what are the benefits of having more oil pressure?


Thanks,
Brandon.

None.
If you have no oil pressure problems then it will do more harm than good. Pressure is an indicator of restriction in the system. You ideally want the minimum pressure that still feeds the bearings, a good guideline has always been 10psi/1000rpm. With fully synthetic oils and tighter clearances it's common to run ~2/3 of that.

i did that to my pinto pump just keeps the relief closed a bit longer that allows a few more psi, so it would really only be giveing you extra pressure at the end of the rev range. not sure what the std relief is set too.. so if you've got an engine that revs a fair bit more than std it would be a good idea