Doing some mods and have a Question

I looking into doing some mods to my 400ex, like a high comp piston, k&n, PC T4 pipe, and some head work. Should I stay with the stock cam or go to a different one? I live in Minnesota. And what would a good jet size be to start at? And should I run a colder plug?
And last question, what oil would be the best for cooling and trail riding and some mud?

Thanks
Tim

[VegasEx'r]

I just put a cam & piston in my 400 & I would recommend a cam if you can afford it. I don't know exactly what jets you should use, because I don't know your elevation or just how cold it gets in MN (I know it's colder than where I live ;) ). If you were to make all of those mods, you might want to start with a 42 or 45 pilot & a 160 or 165 main. I think you'd be okay with the stock plug, and as for oil, I run in the desert & at the dunes, so I can't help there. If you have a service manual, it will give you the oil recommendation based on the temperature where you ride, but off the top of my head, I don't remember what they recommend for cold weather riding.