Eyeglass prescriptions don't work that way. Normal eyeglass lenses don't magnify, they correct vision by decreasing blur. They simply bend light to shift the image focal point to land exactly on your retina (nearsighted people naturally focus in front of the retina, and farsighted people focus behind it). If you manipulate the numbers in your prescription, you'll just be moving the focal point in front of or behind the retina and increasing blur again.
You corrected vision is based on how well your brain can process a focused image, not the numerical values of your prescription. If you really see better by changing the numbers, then you had an incorrect prescription to begin with. To really achieve distance magnification, I think you would need something like the
bioptic glasses used by some people with low vision to read street signs and such while driving.
Robert