You know GSXR, I think you are on to something because I didnt have this problem until I put the Mhead box on, Maybe eventhough I mapped it richer maybe in the upper gears (3rd,4th) it may be restricting it at high range(8-10K) due to the increased appetite. I had the filter on with the half mod box so I didnt think the full box mod would require that much more fuel added but maybe.... What the hell I'll try it. I will map it 10,10,10 and take the filter out and see what it does. Hey Mhead, does you box require that much fuel added? Thanks GSXR!