bear in mind the stock oil temp sensor reads gallery temp and most documentation abotu oil temp is all about sump temps

gallery temps will usually be about 10-12 deg higher than the sump

and you want oil to be at 100 deg C in the sump so 110 in teh gallery is fine
a good full ester synthetic will break down at about 155-160deg C so we're reading it at the hottest point
so I'd go up to the thicker oil for FI but thats it
for a street car in most climates I'd say no cooler is required

Hey Matt, thanks for the reply, nice to know about that 10C difference info. Do you mean oil pan by "sump"?

Yes, i would have no problem if i were seeing 110C at oil sandwich plate (i guess it is right after gallery so temps should be nearly same), but i am seeing 130C after 3 laps with oil cooler. My problem is that i can not track the car, daily driving is no problem, i want to do at least 10 laps back to back.
I am using Motul 0W40 which is ester synthetic. I will try Motul 300V 5W30 next weekend, but i guess it will not help.

I already ordered an obd2 port adapter to and will monitor oil temps via iphone app, it is good to know i need to add 10C to my readings from obd2 for comparison.

yes oil pan = sump

and you said you need to add 10 degrees?
the gallery temp ( where the sensor is ) will be hotter than the sump
so take 10 degrees off to get the sump / oil pan temperature
110 degrees via OB2 oil gallery = 100 degree in the sump
and changing the oil a heavier grade won't make much difference to temperature, but it will mean that the thicker oil maintains more of a bearing wedge at temperature

Do you purge the oil out or just disconnet and cap the lines to the cooler itself with the current oil left in?

I got my obd2 port today and compared oem sensor reading with innovate readings: oem was reading 56C when mtx-d was reading 65C, at the end of some sprited driving oem was reading around 100-101C while mtx was reading 115-117,5C. If i consider gap increases linearly i was at around 113C after 3 laps which is not too bad, so i am a bit relieved but need to see at the track again to be sure.

I just left it in the lines.