Might add that somewhere on the web there's a video of an OHC engine's valve at various RPMs...

Interesting to watch them work at idle and higher revs.

Check out just how long it takes after the engine starts before there is any oil visible around the valves. I also wonder what the ambient temperature was.

[www.youtube.com]

Any idea when that enging was built? Are we looking at 1969 technology or 2009? My first thought was muscle-car engine.

While there have been metallurgy improvements and possibly improvements in manufacturing and oiling the same basic design is still being used, even I dare say in the latest V8 OHV engines from GM, Ford, Chrysler/Dodge.

Have to say it works pretty darn good though of course the rev limit is a bit low compared to OHC engines. My GTO's 6.0l V8 OHV engine was limited to IIRC 6K RPMs (and so was my Camaro Z28's 5.7l V8 and even, and this is a bit of a contradiction, my Mustang GT's 4.6l SOHC) while of course my 2.7l Boxster engine can go a bit over 7K RPMs.

pretty low oil budget topside. They just do not require that much oil up there. You can be sure the camshaft bearings, lobes and the big old hydraulic lifters get plenty of oil. The oil passages that feed these are pretty big.

and at high RPMs the oil becomes a mist/fog. This helps explain why our Boxster engines require so much oil and why there are oil scavenge pumps for each head and these feed their scavenged oil into not one but two swirl pots to remove the entrained air.