After 8000 kms 20 or 30 of the fins on the oil cooler radiator have been flattened by insects or fine stones passing through the grille. I have tackled this issue by cutting out and adhering a black plastic mesh of similar openness to the standard grille mesh. What’s more I have applied mesh to the otherwise bare area where there is no grille mesh at all.
Today I raced the car for a couple of 15 minute sessions at a track-day at Hampton Downs (Auckland) with these mesh panels in place without any noticeable increase in oil or water temperature.