I'm coming up to my change soon and wanted to get a few opinions
Car is an s15 with stock sr20 bottom end. Makes 250kw on 98, it's not a daily so it generally gets a beating when it's taken out.
I tried ten tenths 10/40 and I found the pressure was not stable at all with temp changes. I would thin it out after 5-6 laps at sandown, every session, as well as on mountain runs which put me off. It also caused premature wear of my vct sprocket and had it fail in the matter of months. So I binned the oil after a few friends had issues with the ten tenths also.
Added morose extended and baffled sump with new oil - castrol edge 10/60
it's been superb in terms of pressure consistency and have no issues with it what so ever (street and track)
I now have an oil cooler that I want to add on but I'm thinking whether to switch to a lower viscosity oil as the overall temps will drop once it's on.
Trust thermostatic 13 row cooler -10 lines
Current oil capacity is 6L ... Plus 0.5-1 more for the cooler and filter relocation.
Running oil temps without cooler is 70-80deg , and have only been able to see 95deg on hard mountain runs / hill climb events
Haven't done a proper track day with castrol edge yet
Wondering if there is a benefit in going with a lower viscosity oil , and which one?
And if the oil cooler addition will reduce overal pressure in the system? And how that will affect oil choice
Thanks !