357XP Muffler Mod & RPM's

[ChevyDealer]

My 357XP which i purchased new is an 05 build. Friday I went ahead and cut open my Stock 357XP muffler w/ a hack saw. I enlarged the internal hole slightly in the plate between the chambers to 3/4". Then I drilled a 5/8" hole in the center of the front cover just above the front bracket but only in the front chamber as a second exit. Welded it back up and gave it shot of high temp black paint. I have not put a deflector over the new 5/8" hole yet to divert exhaust flow to the side away from the bar. I have to find a tall deflector like one that came on the saw. Does this sound about right?

Secondly, I tuned it to where it sounded best. I put a tach on it and it was 14300 but I was concerned with that since 14000 is Husky's recommended max on the 357XP. I backed it back off to about 13850 but it is not as crisp. What are your thoughts?

Sorry I didnt snap a pic.

Thanks.

 

[sunfish]

It would have been much better to remove the baffle while you had the muffler apart. I ran one for a few years with extra holes in the baffle & a second port. Did OK, but noticed better gains when I went in and removed the baffle.

I run both mine around 14300-14500... You want to hear a broken up 4 stroking at WOT out of the cut.

 

[ChevyDealer]

Thanks Sunfish. Yes. like I said by ear 14300 was best but I put a tach on it & found I had just tuned it to 14300. So I thought oh no that exceeds recomended max so I better turn it down to be safe. What are everyone thoughts on exceeding the 14000 max spec on the 357XP?

 

[bluesportster02]

Thanks Sunfish. Yes. like I said by ear 14300 was best but I put a tach on it & found I had just tuned it to 14300. So I thought oh no that exceeds recomended max so I better turn it down to be safe. What are everyone thoughts on exceeding the 14000 max spec on the 357XP?

as long as it is not running lean set it to what it wants to run at