Get a 318 or 360 magnum runner $5-600 add a performer airgap intake no need to swap cams, either one will get you 300hp and great mpg. No need to open the motor besides pulling the intake to install the new one. 300 hp is so easy thease days. If you went the 360 mag route with an eddy air gap and TTI headsers 350 hp is doable with out even pulling the valve covers.