hey folx, i’ve been reading ‘which oil’ posts since 2010 & i’m still none the wiser. 
has someone got a definitive answer for a K-reg 1.6 Japanese import?
the shorter the better 
i just need the number, brand & synth or semi-synth.
thank yor
10W40, semi-syn. Brand doesn’t really matter, but FWIW, Millers is ok with me. These days, I pay someone else to change the oil, and the MX5 Specialist I use recently went from Millers to Rock Oil. But I’ve used a lot of Comma oil in the past, which was Esso, but is now Exxon Mobil. I wouldn’t waste money on a fully synthetic oil for cars of this age.
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As above really, don’t over think this, any 10w 40 semi will be fine.
When I say “any” I usually chose a brand like Castrol when I owned my Mk1/Mk2 for oil.
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Totally concur.
I’ve used good 'ol Castrol GtX 5 or 10-30 in both our Mk1 & Mk2.5 for 15 years, and just about every other car for 36 years.
Mk2.5 engine at 105,000 hard miles is still tight, revs like new & clean running…zero oil loss.
All I would say is…change it out either every year or 4/5k miles whichever happens first.
Cheaper than a rebuild. 
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The man from Opie Oils recommends:
5W-40 Fully Synth
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