Are these correct washers for 914-6 case through bolts? The came off our 1970. As you can probably see, they have a bevel on the interior. The OD is flat on both sides.
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When I look up the associated part numbers (901-101-161-01, 901-101-161-02, 901-101-161-03) one side has an exterior bevel. Is this an evolution in design, or do we have the wrong washers?

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Wouldn't you know it. Right after posting this I found the answer. According to Bruce Anderson's Porsche 911 Performance Handbook, the washer I have at top was used on early 911 engines up until the 2.7-liter of 1973.

They were on my 78 3.0. The holes on my case where they sit are beveled too. O-rings sit very nicely in the bevel. I have no leaks! anywhere.

Which 'they' were on your '78 911 SC ?

The 3.0 engine I have is from a 78 911 SC

He was asking witch beveled washers were on your 78 3.0.

Matt

Back to the original question. I never rebuilt a 914/6 engine but did work on several 911's from the early 1970s. They all had the flat case bolt washers as shown in the first picture. I also made a porsche factory tour in 1971 and saw a 914/6 engine next to the 911's on the engine assembly line. Logically, porsche would use the same hardware on the 914/6 and 911 engines.

My washers had the interior bevel.