912 camshaft identification

[Jim Blakewell]

My mechanic, Bob Dumont, built me a '69 912 case motor with 10:1 compression. He passed away and we cannot find any information on the camshaft in the motor. The end has a 10 stamped on it. It doesn't have much lift so seems way too mild for what I wanted. Anyone know which cam I have?
Thanks in advance, Jim

[C J Murray]

You could use a degree wheel and dial indicator to measure the cam.

Unless you intend to rev your engine aggressively you are better off with a stock cam. Porsche was not as stupid as some people think and they always offered 2 or 3 levels of tune with the top level giving away the most low rpm power that Porsche thought would be acceptable to their customers. Also contrary to some claims there is no such thing as a cam that lets you have your cake and eat it too. Cam choice is based on what rpm you shift at most often.

[Jim Blakewell]

I did measure valves. INTAKE .372 inches 336 degrees, exhaust .312 inches at 291 degrees. Dema Elgin said its very mild. I don't want a real peaky motor but good power from 2000- 4000 rpm.
Jim

[Neil Bardsley]

Just seeing this thread now as I was wondering how to measure the CAM in my 912 which is also unknown.

Are you sure about the 10:1 compression ratio in a street engine? Seems quite high. Others will know better but I thought that about 8-9 was more common and friendly on engines?

[C J Murray]

With a degree wheel and dial indicator you can measure your cam in the engine but if you are happy with the performance of your car I would not bother.

[C J Murray]

Yes, 10:1 CR is too high without a long duration cam to reduce pumping pressure/detonation.