This depends on what you want to do.

75 shot or under? Zex dry kit.

Over a 75 shot? Direct port NOS or NX, they are both pretty much the same thing. Or you could get the NOS plate kit, which is a plate that fits in between the two pieces of the GSR intake manifold, and it's similar to a direct port kit. Now I know someone on here is gonna try and say NX makes more power because they rate their kits at the flywheel, when in reality all they do is use bigger jets than other companies and call it the same size shot.