fianly found time to finish my muffler mod on the new husky 359 yesterday. its an 05 etech model.
what i did was cut the muffler in half and completly gut the innternals then used the tubes that the two allen bolts go through to mount the muffler to cylinder as exhaust ports. i cut these tubes off just past the bolt head and then just inside the muffler case on the exit side. yeah it was kinda PITA after cutting the tubes when i went to bolt the muf back on.
what i wanted to do was drill the tubes out and make them larger, but decided id try them as is there about 1/2" inside diameter. then i added another 5/8" hole inbetween these two for alittle added flow. the muffler still has exhaust gasses exiting out the factory top exit in the muffler. so it has three 3 exit points in the front and one top exit point.
after spending a long time welding the muffler halves back together with .30wire then sanding down bird **** weld with flap disc on the grinder and rewelding some again i finaly bolted the muffler back on.
the L jet was right at maxed out as far rich as it would go so i maxed it out and then turned the H jet a half turn richer just to be safe. didnt want to run lean.
with the saw set on choke it burbled ounce i then kicked the choke off and it started right up and idled faster than it used to so i turned the idle down till the chain stop moving. then blipped the throttle. it seemed to acelerate much faster. then ounce warm i opened it up all the way and man i think it runs alot faster on the top end.. i thought it sounded pegged out then i sqeezed some more on the throttle and she kept going.
after this quick full throttle test run i felt that it sounded alittle lean all the way on top so maxed out the H screw against its plastic stop wich was only a half turn more. i dont think it even has full turn of adjustment in it with the limiters in place. these will have to go. i think im right on the edge of being rich enough right now. id like to be alittle richer in the maxed out L side or atleast have the option to go richer.
the modded muffler is much much louder, a guy i know that lives around the block from me came walking over cause hes a tinkern firewood stihl saw running guy and hes like watch got there. lol. hes got a 390. weve got a date to run these two saws head head later on.
i am very impresssed with the added Rs and the quick aceleration the modded muffler provided, though i havnt cut anything yet to see how much if any difrence in the cut the mod will have made.
startn to get Cad, almost bought 16" bar yesterday to. figured then i have 16" bar for camping, 20" for cutn alittle fire wood and maybe doing some work, then 24" when it comes tim to clear a lot. kinda like difrent saw for every acasion.
thanks for all the muffler mod info, Il have to do alittle research on the carb adjustment screws to see what I need to do to get rid of the limiters.
thanks again for the great site
Evan
what i did was cut the muffler in half and completly gut the innternals then used the tubes that the two allen bolts go through to mount the muffler to cylinder as exhaust ports. i cut these tubes off just past the bolt head and then just inside the muffler case on the exit side. yeah it was kinda PITA after cutting the tubes when i went to bolt the muf back on.
what i wanted to do was drill the tubes out and make them larger, but decided id try them as is there about 1/2" inside diameter. then i added another 5/8" hole inbetween these two for alittle added flow. the muffler still has exhaust gasses exiting out the factory top exit in the muffler. so it has three 3 exit points in the front and one top exit point.
after spending a long time welding the muffler halves back together with .30wire then sanding down bird **** weld with flap disc on the grinder and rewelding some again i finaly bolted the muffler back on.
the L jet was right at maxed out as far rich as it would go so i maxed it out and then turned the H jet a half turn richer just to be safe. didnt want to run lean.
with the saw set on choke it burbled ounce i then kicked the choke off and it started right up and idled faster than it used to so i turned the idle down till the chain stop moving. then blipped the throttle. it seemed to acelerate much faster. then ounce warm i opened it up all the way and man i think it runs alot faster on the top end.. i thought it sounded pegged out then i sqeezed some more on the throttle and she kept going.
after this quick full throttle test run i felt that it sounded alittle lean all the way on top so maxed out the H screw against its plastic stop wich was only a half turn more. i dont think it even has full turn of adjustment in it with the limiters in place. these will have to go. i think im right on the edge of being rich enough right now. id like to be alittle richer in the maxed out L side or atleast have the option to go richer.
the modded muffler is much much louder, a guy i know that lives around the block from me came walking over cause hes a tinkern firewood stihl saw running guy and hes like watch got there. lol. hes got a 390. weve got a date to run these two saws head head later on.
i am very impresssed with the added Rs and the quick aceleration the modded muffler provided, though i havnt cut anything yet to see how much if any difrence in the cut the mod will have made.
startn to get Cad, almost bought 16" bar yesterday to. figured then i have 16" bar for camping, 20" for cutn alittle fire wood and maybe doing some work, then 24" when it comes tim to clear a lot. kinda like difrent saw for every acasion.
thanks for all the muffler mod info, Il have to do alittle research on the carb adjustment screws to see what I need to do to get rid of the limiters.
thanks again for the great site
Evan
