Just my humble 2 sen...
You have to know what you want and ask properly... What do you mean by front drive grip?
You want your car to handle better in the corners, or you just want more grip at straight road/launching? Or more traction while accelerating out of corners? All the suggestions everyone posted here are for different things... if you do some self study and ask around with the correct questions, you are more likely to get what you want without wasting money on wrong modifications.
If you just want more grip, 80% of it depends on the tire. Buy good tires, then got good grip. Suspension kong kiau also got grip. The wider the tires, the more grip (Rim size doesnt matter, a 225/50/15 will have more grip than a 195/45/17. However, the lower the tire profile, the more control (less sidewall flex), but the less comfortable).
If you want good handling and traction, now thats a whole different story.
Just to correct a few things here, stiff suspension, thicker anti-roll bars, etc do *not* give more grip.
If you only install a thicker anti-roll bar /stiffer suspension in the front without changing anything else, your car will actually understeer more. You need to increase stiffness in front and at the back accordingly to get good handling. You will get less body roll, more car control, but this doesnt necessarily mean more grip.
If you add camber (not chamber, guys...), it will give you more contact patch when your tire flexes at cornering, hence more grip in the corners. But when on straight roads, you get less grip than having a straight camber.
LSD increases traction, but does not increase any physical grip. Traction = your car's ability to sustain grip on 4 wheels as a whole. Basically, people tune the car to maximize traction, with whatever grip that is given by the tires.