I used a phantom grip in my old car (no one made a real lsd for it) and it worked pretty well. When I first installed it you could get both wheels to spin together on the streets but when I would autocross with slicks it would spin the inside tire. I took it back apart and put in stronger springs and machined the spider gears perfectly flat. This made it work a lot better. I ran it for 3yrs with no problems. ONLY get the phantom grip not some knock off. Also, like em1 said you can get OBX diffs for about $400