As a rule of thumb, the higher you peg it, the more shallow your swing becomes, since you’re forcing yourself to hit up more on the ball. Tee it low and the opposite happens: Your angle of attack gets steeper, because you’ll instinctively swing down more on the ball in order to make contact.
So what’s the right height? From a poll of GOLF’s Top 100 Teachers, the ideal tee height is about 1.5 inches for driver. A good checkpoint is that half the ball “peeks” above the crown after you sole the club at address. For a 3-wood, peg it about half an inch and just a quarter inch with an iron.