Running hot is a complex subject.

Fur is on a dog to keep it warm. Dogs cannot sweat. A dog with fur-on is going to be warmer than a dog with fur-off.

Still, that said, running hot has nothing to do with fur, lol.
Running hot is some combination of "actual temperature" ... as well as condition, blood chemistry, all capped-off with whether the dog is relaxed or stressed.

Temperature affects how long a dog can go;
Condition affects how long a dog can go;
Blood chemistry affects how long a dog can go;
How relaxed/poised vs. amped/nervous the dog is affects how long ago.

Of all these critical factors, whether or not a dog is "shaved" or not is of next-to-ZERO actual benefit IMO.

A shaved dog with shitty blood will still run hot;
A shaved dog in terrible shape will still run hot;
A shaved dog that burns-up all its energy (and/or is full of anxiety) will still run hot.

In the end, a relaxed, poised dog, in shape, and with good blood, will be long-winded with the hair God gave it.

Jack

PS: Can't think of a single all-time-great dog that needed to be matched, shaved