Sway bars can and do help but only if your car is behaving in such a manner as to justify running one. It's not like bolting in a faster motor where more=better. I have run both front and rear bars at different times. I found that front gave me more rear traction at the cost of a bit of steering, and that rear took away a touch of traction but added a bit of steering. I'm not calling that Holy Writ, but that's how my car reacted.