HI Peter,
AS you know I have a ford small block and I sorted the engine cooling perfectly, stays at 90degC both on the street and track.
I have an Earls 13 row wide
oil cooler with a
Oil thermostat sandwich plate that opens at about 160-180deg F.
I use Penrite HPR 30, a 20W-60
oil.
The oil temp on the track gets to 120degreeC but no hotter. On the street it stays at 90degreeC.
Phil