I recently upgraded my LMAs to a spring type (much smoother now!) but during that teardown I noticed that oil in the cam bores was noticeably darker. The head was clean looking and I saw no galling or other damage but I was wondering what it could be.



My thoughts are oil pressure related, since my warm idle oil pressure seems low (around 20psi) and the oil light at startup takes a few seconds to go off. The car runs great once warmed up and oil pressure is fine up to redline (90psi). My next steps are to take a look at the bottom end, replace the oil pump and oil squirter bolts.

My last 3 used oil analysis reports have come back clean but I'd like to understand if theres something going on here.

 

I would expect that area of the head to have the highest heat output since that's exactly where the camshafts are making direct contact. That metal is also more brightly polished than the surrounding parts, and forms a valley which could impact the way the oil looks aesthetically while sitting in it versus the rocker arms and other spots.

Not sure if what you're noticing is excessive or not. If there's no damage or scarring on the cams and the oil is otherwise clean I personally wouldn't worry about it.

 

Thanks, I see what you are saying about the polished areas and how they can exaggerate the color of the oil. It all looked clean otherwise so I won't worry too much. Only other thing I'm concerned with is I don't recall seeing a o-ring under the center cam cap (there should have been one as I understand it, it was probably stuck to the cam cap), so I'm waiting on orings to replace that and the rocker shaft orifice orings, then hopefully I can leave the top-end alone for a while.