Discussion and technical advice the SW20 MR2. 3S-GTE, 3S-GE, 3S-FE etc
Anything and everything to do with maintenance, modifications and electrical is in here for the Mk2.
I would be using a high quality ester synthetic of at least 10w40 ideally at that power maybe go for 10w50. You will pay at least 50 for 5 litres I'd have thought.
The power is completely irrelevant. More important is how much play is in the bearings/pistons/shafts and how cold it gets where you are.
A 60 weight oil is still pretty thick at higher temperatures and lends itself well to forged motors with 4032 alloy pistons or older motors with large clearances.
For all others I would suggest 40 or max 50 weight oil.
The winter index in most parts of europe i good enough with 5 or 10.