I bet it'd go even higher than 240 degs....especially with 50/50 mix, 240 is only 28 higher than normal boiling temp.....then again, I don't really want to find out.
Highest mine's ever gone was uphill in 85 degree weather in pennsylvania, floored in third gear with 1100lbs of cargo and people up a hill, it was only making about 35-45mph tops depending on the grade, those were such steep hills!
It got up to near 110C for a little bit, but fell right away when going down hill.
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