Ok putting together my undertunnel exhaust. At first i was going to put the muffler directly underneath where the Seat mount is. Now im debating making the mid pipe shorter and putting the muffler directly under where the seat is so the outlet would be where the seat mount is. So whats everyone else done on how far back there muffler is. Any pros or cons to having it longer or shorter?
Nytro Undertunnel exhaust length.
- Thread starter philsummers21
- Start date
I am working on this right now too. What muffler are you going with?
I have an Excell header and will probably use a glass pack muffler. The muffler is about 22" long. When I mock this up, the outlet of the muffler is approximately were the steel brace behind the seat is (where the original muffler bolted to). I plan to leave this support in and hang the glass pack from it. I don't have all the details figured out yet.
Are you changing your seat support too? I plan to keep the area under the seat open and try to find a pack that will fit under.
I have an Excell header and will probably use a glass pack muffler. The muffler is about 22" long. When I mock this up, the outlet of the muffler is approximately were the steel brace behind the seat is (where the original muffler bolted to). I plan to leave this support in and hang the glass pack from it. I don't have all the details figured out yet.
Are you changing your seat support too? I plan to keep the area under the seat open and try to find a pack that will fit under.
I have a 2 brothers Carbon Fibre oval exhaust that is cut down to 10". I just used the stock header cut off the mid pipe like 1" past where the 3 go into 1. Then made a straight pipe that goes to my muffler. Right now im hitting that brace for the old exhaust so i either need to move muffler back 4 more inches or bring it forward about 8 Not sure what way i want to just yet. Probably end up going shorter since i would have to remake a longer mid pipe. Then if for some reason i need to extend it i can then. Im keeping the seat support the same.
What im going to end up doing is cutting that mid pipe shorter and placing the muffler inside the center cutout hole near the back of the hole.
my only thought of going shorter is that it will be easier for the snow to plug up exhaust in deep pow and bog the sled down. Might not be the case with the four stroke tho. I guess if that happens i can make a piece to block the snow from going into the exhaust.
It will be a problem. You will need to do something about it.
A
I am also doing the same thing. I am using a Yoshi RS-3. i am going to use the brace where the stock muffler mounted to for a hanger on the inlet side of the muffler and then I am going to add another brace in the back of the tunnel by where the tail light is for a hanger on the outlet side of the muffler. This should slove any snow injestion issues. I like that cut down 2 bros. Looks cool.
K finally got it all cut to my length tacked in place where i want it. Will weld it all up tomorrow and install it for the final time. Will get pics tomorrow. By the way the whole exhaust setup weighs in at 7lbs. Header, midpipe and muffler. Thats lighter then the old muffler just by itself.
Well finally got around to putting the sled mostly back together. Started it up and the sound is amazing, BUT its a little loud. So hopefully after i get the tunnel block off plate and seat on plus out of the garage its not too bad. Hopefully OFT will have some news on there tunnel block off plate fairly soon.
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That looks like it is turning out pretty good. I think once you get a tunnel block off and its out in the snow it should quiet it down a little.
M
Didja ever finish Phil?
Sure did. I suppose i can post up some pics, expecially of a very nice tunnel block off. Tomorrow plan on putting on the CAT footwell outer pieces and cut off the back 1/3 of my running boards. Going to go do a test and tune run saturday if your bored moto make sure everything is ready for the winter.
heres some pics of the exhaust, OFT Relocator, OFT Tunnel Block and the CAT rail pieces that will go on tomorrow.
Looking good Phil:beer;
I should post a pic of the Roll over valve as well. What a spectacular piece. Definatly a must for any Nytro owner. Hopefully for Xmas santa will deliver a Timbersled suspension for me.
Looks good! I like the cat running boards I already bent mine though and I have only 2 days on this sled. I dumped my exhaust out of the side of the tunnel to avoid any snow issues. Have a Skinz seat ordered to clean up the top side.
B
Looks sweet
Thanks Phil, I try to build'em to appear and perform just like a factory OEM part!
