At HPR cooling is THE BIGGEST challenge. It is east of Denver, in corn country (literally) where summer temperatures are around 100f and altitude is 5,000ft. All VW’s have issues here. GTI, R, doesn’t matter. Without radiator type oil cooler, or two, you are running 2-3 laps and then it is limp mode time.
I had to install N55 radiator type oil cooler as my oil temperatures would go to 300f.
Luckily I have N52 and manual, so oil cooler from N55 is overkill. I have seen tuned 335 with two huge, 25-27 row oil coolers, and still having issues.