At the grate or on a pit therm mounted on the side of the drum?
Grate temps will be 25-50*+ on the grate. Just sick a couple of Polder probes at various spots on the cook grate and watch the temps fluctuate.
That is if he's cooking direct, which I'm assuming he is since its a UDS and using a heat sink would be blasphemous, and I'd recommend foiling the ribs anyway....
I'd turn them every half hour or use a rib rack if you don't want to foil.
Brian - Left Hand Smoke BBQ PNWBA 2010 Team of the Year
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