Do you have a PCV system ? If not, they can help a lot with pesky
oil leaks on a SBF.
even with a PCV system that is working good, and with no blow by issues as you state, SBF are well known for crankcase pressure issues. I can go for weeks without any
oil ooze. But a few minutes of redline activity almost always shows up as a slight, and temporary, rear seal leak.
Z