While the notion that a valve rotates is a commonly accepted notion, it is not supported by the engine monitor data
Really?
http://www.fev.com/fileadmin/fev-res...Techniques.pdf
I was lazy and just asked my friend google and picked the first paper I found. But you can follow through the references if you like. These date back to 1951.
The best engine guys in the world are Ricardo plc (English HO), AVL (Austrian HO) and FEV (German HO). These guys do most engine development in the world, although they can be very discrete about clients. Their clients frequently claim work done by these companies as their own. One of my fiends worked for FEV in Detroit with one of the US big 3 who were claiming the FEV work as their own. If you go to the Ricardo library in Shoreham you can see some of the lengths they go to in order to protect the identity of clients who request it.
Ricardo is head-quartered on the same Estate in Shoreham where Sir Harry Ricardo lived when he invented the Octane rating. Go there and you will see 50 engine test cells running 24 hours / day. I believe AVL has more. Even sleepy Orbital in Perth has a dozen.
The best engine test cell hardware & software is made by these 3 who sell engine test cells to the car manufacturers.
20 years ago (or more) even Gibson Motorsport with their 2 dyne facility in the back of the race workshop in Dandenong was doing intra cylinder pressure logging of their race engines (I have the sensor they used) and some work on combustion photography.
Go to Engine Test Expo in Stuttgart in June and you'll see rows of companies specialising in engine test sensors to study things like this. Its a whole industry.
Its only aviation that is still discovering these concepts. In fact, its probably really only MCI & Lycoming because as John Deakin points out P&W pretty much had it figured out several decades ago.
One of the real problems with aircraft engines is that valve seat design has not kept up with modern technology. I'm convinced that a significant part of the Continental disease is just poor, old fashioned valve seat design & valve metallurgy. My hypothesis is that a lot of the valve seat recession that is seen with Continental cylinders and blamed in mixture practices is just poor seat profile and poor valve head metallurgy.