[Kube]

Dan, I have never seen any lower temperatures running George's pumps. Of course, my engines are all properly rebuilt along with all of the accessories (carb, pump, distributor...) as well as having the radiator re-cored.
Still, I have him do all of my pumps as he does do beautiful work at a very reasonable price.
I think with careful study of any and all replies, you'll quickly realize the guys that saw an improvement were simply adding a "band-aid" of sorts and helping an otherwise lacking system and / or component(s).

It sounds as if you do properly rebuild your engines and related components. That makes me wonder if the engine is still "tight" (fresh) and you need to run it more.