Yep will definately have to get a lsd to get full potential of the sc and the peak power will be minimal/ if any, but we have to remember that the EM1 is a biggish car almost the same size as a teg but has the smaller b16 which is still great but that extra torque that the sc gives will give it the edge that it needs, bigger supercharger or small turbo setup would be good as well but its not going to be a full on track car so everyday driving is another "obstacle" that has to be looked at when building it, plus turbo you would possibly have to do an engine rebuild do you can get some decent boost and its an added cost for whats basically a great streeter thats going to be going to track days.
Also theres good bolt on's and plus a good tune that will help with peak HP but another thing that has to be considered is the handling setup for road/race car thats going to be emptying the pockets as well, so for the power it gives and what its worth its good to do