Well, technically speaking, lowering the car is irrellevant. Lowering lowers the average road height, but it doesn't lower the minimum road height. That being said, when you lower, if you do choose wheels which MIGHT hit with the stock wheels, they will more likely hit with the lowering springs.
Really you do not want to change the overall diameter of your wheel+tire. If you tell me what wheels & tire size you have, I could tell you what that is. To change it would change your speedometer & odometer, plus an increase would make you far more likely to hit.
Really you do not want to change the overall diameter of your wheel+tire. If you tell me what wheels & tire size you have, I could tell you what that is. To change it would change your speedometer & odometer, plus an increase would make you far more likely to hit.