you dont need to swap the cam, you actually dont need to swap anything, I had Mack update my 04 AI427 to get rid of the stumble on takeoff (and yes it is a no charge mack update for those engines) and when I got it on the road it was worse than when I went in, the stumble was gone but so was all the power it was sick. I went back and bitched the service manager out so they flashed it again with a new program from PA this one was better but still not enough for me so I went back and told em to keep the P.O.S. i would go buy a KW and then bitched out a guy in PA on the phone, so they sent another flash for it(staxx put it in) and after that I dont know how much power it made but it would run right with a 475 CAT, pass a 460 on any hill, it would black smoke if you lugged it down and make 38-40psi of boost and just pull like hell all the way thru the power band. My point being the parts are good for plenty of power you just ned the program to make it run right.