MM are you talking orange juice, or like triple sec??, if it's orange juice dear god, your liver must be dying, i do more like 1:5 if its orange juice, other wise it tastes pretty much like only vodka to me, of course after ive drank a few i may ttake it to like 1:3 but thats the most i would do really.
A Screwdriver is 50/50 vodka and orange juice. That is the only way to make it and the only drink you can properly call a Screwdriver.
A Vodka and orange is usually anywhere from 4-6:1 (basically cordial ratio). In Australia the standard for vodka and orange (or borbon and coke, gin and tonic, pretty much any mixxed drink) is 6:1 which is one standard shot (30ml) in a standard small glass (200ml).
Fruit juice is great at relieving hangovers, the problem with drinking less than a Screwdriver is that the next morning a glass of orange juice tastes exactly the same so you are forced to drink some other juice instead. With a Screwdriver you can taste the alcohol and the morning's orange juice tastes like it should.