2010 impreza

May 28, 2023
I have a 2010 impreza 2L NA.

Its my sons daily driver/QLD raceway, lakeside track thrasher.

Engine wise std, 190K on it. Currently running 10w 40 Penrite 10 Tenths. Track days in summer on the track oil temperature is 110 degrees and oil pressure 100 plus psi. At idle oil temp was around 102 and pressure was around 30 psi.

On the street oil temp in stop start 105 ish, oil pressure 90 ish while driving, at idle 105 ish psi, oil pressure 30 ish. At a constant 100/110 kph oil temp 110 degree, oil pressure 100 psi.

Is 110 degree oil temp a problem for prolonged periods?

My understanding of oil viscosity is very limited so if some of my questions seem dumb please forgive me.

Next summer if I change to a lets say a 10w 50 (group 4 or 5 based oil) will that protect the engine more on track days given the higher viscosity? It really cops maximum rpms lap after lap and on the street (P plater)?

Next week its due for an oil change so I am trying Nulon 5w 40 Race in the black can. My thoughts are the 5w will be better for cold starting in winter? Why am I using 10 tenths, Nulon race? They are group 4 based and have high zinc content which I believe helps protect the engine.

Any suggestions on brands to try or stay away from? Cost is not an issue.

An oil cooler will be installed before next summer.
The n/a subies don't tax the oil as much as the turbo subies....with that said, any car that sees track duty, id throw a oil cooler in.

With that said.....if you track a subie, the best oil cooler, best oil won't help you if you run the stock pan and pickup.

Hit up Killer B for a pan/pickup.