Originally Posted by totopo

On a like ~90 degree day at acs I hit like 230 on warm up, 265ish after first full lap (usually best time) then close to 280 after 2 more full laps, where the engine is noticeably slower, then ran a cool down lap after 3 green laps which usually got it to the 260-265 range. The stock oil cooler definitely does not cut it. I would strongly recommend you plan to have cool-down laps unless you are stuck behind traffic. For a 20 minute session I think I got usually like 5-6 full laps in, not counting first warm up and ending half a lap after checker. So I did warm up, 3 laps, cool down, 1-2 laps, checker i think. Probably better if you plan warm up, 2 laps, cool down, 2-3 laps, checker. I would also recommend you treat your warm up lap like a warm up and not to go crazy and overheat your engine on a useless lap.

According to motoiq, 280F is bad

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edit: apperently can't link to motoiq? just search for their 370z project car.