O200 camshaft -- valve overlap / timing?

O-200 Camshaft

Maybe somebody can help to find my peace after a lot of years, asking hundreds of so called experts and after paying 12k$.......
years ago I rebuild my 2nd PA-18 with a O-200, 0h, freshly overhauled in the US and shipped to Germany. It was mounted in and right the 1st test run showed an abnormality, at full throttle 2100 RPM the engine was running rough and was shaking & stuttering. When I pulled the mixture a little bit it ran smooth and ground RPM was about 2150 with temps in the green arc. Changed Carburetors with different settings, Propellers with different pitch, checked the Primer pump, the gap in the air box, fuel flow, valve springs, mag's etc. nothing at all...............
I contacted the deliverer in the US, with a few words, the 2 brothers at E........ton refused the warranty. I flew the PA-18 for some 150h and finally I had to take off the engine, replace the 2 burned cylinders and it was converted to a C-90-14F and it ran fine after.
I never found out the reason of that symptom, not even the shop who did the conversion could explain that. My thought was, that there was mounted a wrong camshaft as for an engine for industrial use or similar. even if the Camshaft showed the right P/N according the Overhaul manual. Now, after years, reading about the valve overlapping due to a wrong Camshaft.... this could be the reason why!
Had somebody had same or similar problems????

Who rebuilt the engine?

1st time was rebuild in the US, a shop at Elisabethon and 2nd time near Frankfort/Germany.
The C-90-12F of my 7-EC and the O-320 PA-12 were rebuild by Ole Joergensen, Padborg/Denmark, never had any problem with them

O-200....full throttle....2100rpm?
I'll bet if I had a prop on my O-200 that only let it turn 2100rpm static that it would be very unhappy.....
I would suspect that the C90 cam would be happier at that static rpm (but it still seems pretty low ...)
DaveG

............can you imagine how unhappy I was, due to a new, never running as should engine & never making more RPM.........

reviving old thread here...does anybody know where you can get dimensions of the 0200 or c85 rockers..or does anybody know the ration of these

Just saw this old post. Rocker ratio is 1.2

What about the new O-200 cam 643067?

This old post almost gave me the answer I wanted, but not quite. For the numbers that Continental gives on valve duration and overlap, does anyone know how that is measured. There are a few different ways that it can be measured as pointed out in a previous post. I.e. right when the valve comes off the seat or 0.05" after it comes off the seat which is now somewhat standard when measuring duration and overlap, but was it back then? 0.05" can make a big difference on the angles... It would be nice to know how Continental measured duration and overlap on their A65, C90 and O-200 cams. Anybody know for sure?

For what its worth... With an optical comparator and an A-65 cam we figured Continental's duration and overlap numbers are based on lifter lift at 0.006" (which actually happens to be an SAE standard currently, probably taken from some previous standard Continental used). So with the rocker arm ratio of 1.3 that would be about 0.008" of valve lift. I won't go into why this was important to me because I am likely talking to myself on this post. But now its here in case anybody else comes googling for it.

Central Cylinder Services at Omaha, email CCS@CentralCylinder.com, used to build 0-200 air racer engines, Maybe they still do. I know that 15 years ago they had very knowledgeable people there regarding the C90 to 0200 cam change. They might be able to provide more specific cam info.

Good luck.