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912 BBS - Welcome to 912BBS
If I recall correctly many recommend using old school oil, 20-50w.
Synthetics can easily leak out, but not necessarily.
I think I am using Bosch plugs on mine. Shouldn't be too hard to find. Naturally other makes will work too.
These options from Pelican : ( 2.0 liter 914/4 uses the same engine )
Porsche 914 Ignition Tune-Up - Page 2