I was fighting a high speed miss all last year. After talking to Guy at the TX race last year he decided it was valve springs. Over the winter I switched to his newer design cam and springs and NOW the miss is history! I should have listened to others all year but just didn't think a 5200 rpm motor needed a bunch of pressure with the little valves. Well It did! I was also worried about switching the cam because of spool up. My old setup would spool a single with no trouble at all and I was afraid to loose that. Guy promised that the new cam would spool the same and it did. I can not thank him enough for a product and his knowledge that got me back on track. I have been testing and the numbers look to be awesome! I can't wait for TS next week.