Cooking experts: What are the cooking times for various weights of turkeys with the dressing in it?

I cook my fully thawed turkeys with dressing in it at 450 °F sealed in aluminum foil. I throw away the timer and I don’t open it at all until it’s done. I’m trying to develop a simple chart with a sliding scale so can take the turkey weight and cross reference it with the cooking time when I bake it. I usually bake a 20 pounder for 3 1/2 hours and it comes out perfect. I did a 17 pounder once at about 3:06 and it came out perfect. However when I did a 24 pounder at 4 hours (my straight line estimate) that wasn’t enough. So maybe a curve would be better than a straight line. However I really don’t know. If you have worked out perfect cooking times for various weights of turkey with dressing in it I’d like your input. It doesn’t bother me what temperature you do yours (350 °F or whatever) as long as you have worked out the perfect time for cooking all your various turkey weights while cooking in a similar manner to the way I do. It would give me useful information that I could work with.