I've got a DMC exhaust, KaN filter with no lid, and WB rev box on my 400EX. Now i want to either get the 426 kit or a bigger cam for it. I'm not really sure which one to get first? I can get the 426 kit for less. What would be a good cam for more mid-top end power? And what kind of price am i looking at for a cam/springs? Do you have to get the hard-faced rockers also? Is there any place you can get a cam with out the core charge? I'd like to keep my stock one just in case i don't like the power delivery of the other cam.

 

you could get a factory xr400 cam. runs about $180 and you would keep yours and not have to hardface anything. Just drop it in.

 

what's the power increase with a xr400 cam