I would like to put a larger jet kit in my 800, i would also like to check out some performance cams but haven't been able to find anything!
Start with a Dynojet kit.
By the way what are you running for exhaust on your bike? If you have the stock exhaust you might want to consider something aftermarket that breathes a little better and then put a K&N filter in. I just came back from a ride on my girl and I'm really pleased with the performance. I'm running straight pipes with baffles in them, a K&N filter and I did the dynojet kit. I think my bike is fairly peppy for an 800 v twin.