An MS 441 running with a 16" bar? Are you sure that you haven't then created a Hemi 'Cuda, an Olds 442, or a Dodge Viper? Gasp!Just get a 16 or 18 " es bar & a 9 pin rim sprocket & retire the thing to limbing . Tune it for 13500 13800 rpm . Save your money up for a 650 or 660 then dual port it. Much better than spending a lot of time & money on expermental questionable gains