@Nuvolarix Frankly, I don't see the value in knowing the specific grip dropoff, it's very sudden and massive, so you don't ever wanna be outside the working range. It doesn't really matter much beyond knowing that.
...that said, since you're asking for it, I'll post it anyway. I won't do celsius conversion this time, sorry about that.
Surface (C5-C1):
<SplineElement x="323.150000" y="0.910000" />
<SplineElement x="328.150000" y="0.928000" />
<SplineElement x="333.150000" y="0.946000" />
<SplineElement x="338.150000" y="0.964000" />
<SplineElement x="343.150000" y="0.982000" />
<SplineElement x="348.150000" y="1.000000" />
<SplineElement x="388.150000" y="1.000000" />
<SplineElement x="393.150000" y="0.962500" />
<SplineElement x="398.150000" y="0.925000" />
<SplineElement x="403.150000" y="0.882500" />
<SplineElement x="408.150000" y="0.845000" />
<SplineElement x="413.150000" y="0.825000" />
<SplineElement x="418.150000" y="0.810000" />
<SplineElement x="423.150000" y="0.800000" />
Core (C5-C4):
<SplineElement x="346.900000" y="0.935000" />
<SplineElement x="350.650000" y="0.970000" />
<SplineElement x="354.400000" y="0.980000" />
<SplineElement x="358.150000" y="1.000000" />
<SplineElement x="373.150000" y="1.000000" />
<SplineElement x="376.900000" y="0.960000" />
<SplineElement x="380.650000" y="0.920000" />
<SplineElement x="384.400000" y="0.880000" />
Core (C3-C1):
<SplineElement x="346.900000" y="0.920000" />
<SplineElement x="350.650000" y="0.960000" />
<SplineElement x="354.400000" y="0.980000" />
<SplineElement x="358.150000" y="1.000000" />
<SplineElement x="373.150000" y="1.000000" />
<SplineElement x="376.900000" y="0.965000" />
<SplineElement x="380.650000" y="0.930000" />
<SplineElement x="384.400000" y="0.895000" />