I just put the AAEN long duration cam for the Scrambler in my H.O. Sportsman. Improves mid-range performance, but I want more. I have tried an AAEN megaphone muffler with a Supertrapp Spark Arrestor, but what the megaphone gives, the Spark Arrestor takes away.
The head pipe is about an inch and a half in diameter, but the little stubby tail pipe is only
an inch in diameter. What happens when you change that? An easy welding project, replace that stubby little tailpipe with an inch and a half diameter tailpipe. Especially with this cam, I think I'm choking any top end improvement with this muffler, but I don't want it any louder. I believe in stealth, sometimes I ride places I'm not supposed to be. I have a white clutch spring and a K&N air filter. By the way,
do not be afraid of this cam. It is very smooth, not peaky, idles and starts fine. I may be inclined to use low range more often, as I should anyway. It took 2 hours to swap cams, the sportsman is a little harder to work on than the 425 EXP was, as the engine in the SP sits a little farther back and it is a little harder to get to the bolts. Still, no biggy.
I think the Polaris muffler is a good unit, but I think it can be tweaked for a little more top end. Any thoughts???
Silly Later,,,,,Fourlix

 

I thought it was 1-5/8" pipe?

I've thought the same on outlet size myself.

Try Greg's airbox stuff first, then coat the head pipe. This keeps the velocity up. Then, Id try a 2" outlet. if you're gonna change it, you might as well do it right!

Gotta get air in if your gonna get exhaust out!

 

how much did you pay for the cam? do you think its worth the money for the gain?

 

fourlix,

I tried modifying my stock muffler. The only way to really increase the flow is to put an outlet on the back of the muffler. If you were to cut the end of the muffler off you would see why. There are at least four chambers that the exhaust has to flow through to get out. The paths from chamber to chamber are not the best for flow either. You can put an outlet on the back of the muffler and bypass two of the chambers if I remeber right. The only problem is that the bike will sound very weird. It will have a whistling sound. It is also quite a bit louder. It does help though. I could not ever get it to sound good so I abandoned the idea and bought the supertrapp. Sounds alot better and works good too. It is louder but if you do not get on it you can sneak around.

On another note, when you put the HO cam in your sons Xped do you think it lost any low end? I am looking to do some motor mods to mine and wondering how the cam affected his. Also did you change anything of the jetting or just leave it like it was?

 

The cam cost $259 ouch! the H.O. cams are going for around $159. I don't see any reason to not use these cams. The loss of low end is negligible, mid-range increases are good.
But I think Greg has the right idea. Engines are pumps, more air is more horsepower. These air boxes are too restricted, open them up, stick a cam in, open up the exhaust, Jet them right, now we're talkin' horsepower! I wish I had an old Polaris muffler to disect and figure out how to open it up a little, a few extra holes in the right places. I want 70 mph out of my H.O.
Silly Later,,,,Fourlix

 

How about a cut-out? You know, like whiskey runners. A second pipe straight out the back with a butterfly valve on it. Close it up for stock sound and performance, or open it up!
Silly Later,,,,,Fourlix

 

Hey Fourlix, a few questions. You said the HO cams were 159 bucks, and your aftermarket cam was 259 bucks. Then you said You see no reason not to use these cams. Im confused. The 159 dollar cam is a stock polaris cam for the HO? Which cam are you recommending here bud? Did you seem to loose any top end with the cam? Im like you, I want more power from my HO, not more noise.

Later,

Dave

 

guys the old glaspak mufflers make a great muffler for your sp500. there are two kinds .loud and quite paks. the quite makes a great choice. very easy to make fit.you can cut all the brackets from your stock muffler and weld them to it.i even added a stainless chevy bowtie to mine.looks great.sounds great