Did a muffler mod on 346xp NE. There are many ways to do this but I thought I’d take pics along the way and share my method. This is pretty easy and may help some of you who want to do a muffler mod. I wanted to enlarge the stock port on the non-cat muffler. To do this, I decided to remove the stock deflector (so I could open up the port) then add a 288xp deflector (#503589901) to finish it off.
First, remove the muffler and take out the screen. You can add the screen later if you wish. I chose not to reuse it.
Next, place the muffler in a vise and drill out the spot crimps that surround the stock deflector. This will help it come off later. I used some needle nose pliers to remove the stock deflector by twisting the metal and pulling it off. (Be careful not to warp the muffler or cave it in while twisting off the deflector)
Next, test fit the new deflector and trace your desired opening. Note: you can reuse the stock screw from the screen on one side. (You’ll have to drill a small hole on the other side and install another screw)
Then I took a dremel tool and grinded out the new port. You'll have to grind the remaining deflector flat in order to prep the muffler for fitting the new one.
Take a screwdriver and insert it into the opening and pry upward so the new port will make a good seal for the new deflector. Also, it helps if you use some pliers to bend the new deflector edges to the correct shape to cover the port.
Finish up and smooth out the new port and test fit the new deflector. Make sure you blow out all the remaining metal flakes from the muffler. Use some high heat paint to cover the grinds. Make sure you take your time and make adjustments until you have a good fit. Don’t over tighten the new screw so you don’t strip it. I used a bar guide screw (#503212810) for the second hole.
First, remove the muffler and take out the screen. You can add the screen later if you wish. I chose not to reuse it.
Next, place the muffler in a vise and drill out the spot crimps that surround the stock deflector. This will help it come off later. I used some needle nose pliers to remove the stock deflector by twisting the metal and pulling it off. (Be careful not to warp the muffler or cave it in while twisting off the deflector)
Next, test fit the new deflector and trace your desired opening. Note: you can reuse the stock screw from the screen on one side. (You’ll have to drill a small hole on the other side and install another screw)
Then I took a dremel tool and grinded out the new port. You'll have to grind the remaining deflector flat in order to prep the muffler for fitting the new one.
Take a screwdriver and insert it into the opening and pry upward so the new port will make a good seal for the new deflector. Also, it helps if you use some pliers to bend the new deflector edges to the correct shape to cover the port.
Finish up and smooth out the new port and test fit the new deflector. Make sure you blow out all the remaining metal flakes from the muffler. Use some high heat paint to cover the grinds. Make sure you take your time and make adjustments until you have a good fit. Don’t over tighten the new screw so you don’t strip it. I used a bar guide screw (#503212810) for the second hole.