Hey guys another rookie ??? .. When I bought my 914 the PO said it was a 2.0 when a next door neighbour thinks it's a 1.7 .. I'm hoping the serial number is still on the engine and hasn't been tamped with .. Where would I find it on the engine and is there any other things or diffiranses that point out the two engines ..? Thanks Again

The serial number would only confirm the engine case was either a 2.0, a 1.8 or a 1.7. Either of these cases could have been built into a 2.0.
Look at the angle of the spark plugs and the number of intake manifold bolts. 3 intake manifold bolts would indicate 2.0 liter heads

This may help in finding the actual number (the other white arrow in both pictures):

1.7L & 1.8L


2.0L

This is what a 2.0 liter head with 3 intake manifold bolts looks like.

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