I know it is a long shot.
I have started to model up a 4.5 liter 12 cylinder 917 engine. I am using a few drawings I have found online and pictures. For scaling purposes I have used some known dimensions like the stroke (66mm in this case)
There are some components that would be nice to get better dimensions from such as bearings which if they shared 911 bearings that wouldn't be too difficult to obtain the numbers needed.
The final goal is to have a 3D model so that anyone could print or machine a scale version of this engine for their own enjoyment!
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