so i had my car retuned a few weeks ago and the tuner noticed oil temp was consistantly high.
when it was last tuned and driven oil temp would sit at 80 degrees and now it sits between 90-100 when cruising at 100kph.
before the tune i switched from motul turbolight to penrite racing 10 10w40 and tidied up oil cooler (flipped how i installed it and moved temp sensor in line)
once the car has sat off for 10-15mins oil temp is back to 65-70.
engine:
built rb25 (2000km old, built by red r racing about 4.5 yrs ago) 6boost, gt3076 .82ex, greddy plenum, 1000cc xpurts.
nitto oil pump, rb20 oil block, mocal thermostat oil block (group buy kit), 19row setrab oil cooler (sits behind a opening in front bar), z145a filter
tuner has told me to use a thicker oil to see if that will solve the problem but i can't see how its gone from running normal to hot.
could there be another issue or changing the oil type will make that much difference?
and what oil should i try next? looking at penrite hpr10 10w50 or go back to motul?