AnyBody ever split the muffler on a 500 scrambler and gut it or drill some holes in the baffling to let it flow better if so did it help??

 

THat would be a no no.

 

Why would that be a "no,no"??? It will not hurt anything. I have knocked out all the baffling in my stock pipe & it did improve the power a little. However, the word little being the key word. I would say more so throttle response than actual power increase. The sound emitted is hardly louder than stock, so it won't offend the tree huggers,police & cry babies, and is a cheap way to get just a little edge on the competition while still looking stock.

 

Thats why I,m wondering if anybody has done this on Polaris snowmobiles there were big bore kits that had you do this to the exhaust and it would be more critical on a 2 stroke than a 4 stroke

 

I say go for it, if that's what you want. You won't have to re-jet, if that's what you're worried about. The way I did mine was by taking the muffler off of course, and when looking into the inlet end of the muffler, I took a long drill bit & drilled into the center of the "solid" looking piece that's about the size of a quarter. It looks solid, but it's not. Once you have the pilot hole drilled thru, take rod, or bigger drill bit if you have one, & open the hole up to the same size as the tube you just drilled into & now it's a straight shot all the way back to the end & then out the turn down.

I hope I made sense & you understand what I am describing.

 

From my Harley experiance I have found that a full flowing exhaust works best twith a little abstuction.IAnd the same thing is with any 4stroke motor.But I may just be a dumd ***

 

No, you're thinking right about back pressure on four strokes. I may be wrong here too, but the little 1" outlet on the stock 500's muffler should be more than sufficient backpressure for the engine, considering that the header & inlet to the muffler is double that, even if the baffles are gone.

 

Ok just to play "devils addvocate" here how come race gokarts with 4stroke mtrs have straight pipes and drag cars and circle trackers all have open headers does an open pipe take away from the low end?? I can see how the 2strokes need back pressure to close off the exhaust port but a 4stroke has a valve to do this not trying to argue just trying to learn something

 

On race cars they run open pipes because they dont need the lowend all they want is Wide open power.Even with that they run tuned headers that help the flow out of the head.

 

I just did this mod on my Sportsman 500,i welded up the 1" bottom pipe,cut the end cap off,then gutted the back end and then welded the end cap back on and cut out a 2 1/2" hole out the back and added a 2 1/2" piece of pipe.It sounds very good.