Too many variables for there to be one set answer. Racing weight really does not factor in IMHO.
For example; I have one male who raced at 72 pounds. Now, as a pet, he weighs about 75 pounds and looks good. He is a very muscular hound with a powerful build.
I have another male who raced quite successfully at about 76 pounds. He weighs 82 pounds now and would be o.k. with another 2 or 3 pounds. He raced very lean. There was no arguing with the success he was having at that weight so he stayed there. Now, as a pet, he looks great in the mid 80 pound range. He is tall and lanky.
For comparison, I also have a tiny little female who raced at about 57 pounds. Now, as a 7 year old pet, she weighs around 62 pounds. She just looks at food and she gains weight. No point in starving her to keep her at "race" weight. She is not a racer any longer. I keep her as trim as possible, but within reason.
All of my dogs get a lot of exercise. Muscle weighs more than fat and all three are quite fit. If your
hound looks good (not soft or fat) and feels good that is really all he needs to be.