PoulanPro Muffler Ports(?)

[lxskllr]

I had already removed the spark arrestor from my PoulanPro, and decided to take the top cover off. It's louder now, but I haven't cut enough to know if it has anymore power. It has a primary output slot where the exhaust seems to vent, as well as two tubes that are pretty clean. This is what it looks like more or less(not my pic)...

The ports were covered by the plate, but didn't seem to be sealed. Questions; What do the ports do, and is it bad to have them uncovered?

Edit:
I think I found what the tubes are for, but I'll have to check. Found a thread that mentioned it in passing, and I think it's where the bolts are that mount it to the motor. If that's the case, they're nothing.

 

[Magnus]

I think that could be right. What model Poulan pro is this you have?

 

[lxskllr]

It's the PR4218. I had gotten NIB from a pawnshop for $75 to replace my ms362 that got stolen. I figure cheap is good, and I had a positive experience with my previous PoulanPro. This one feels cheaper though, and we got off to a rocky start. I couldn't get it tuned right, and one of the last things I did was slam it on my tailgate before putting it away. My replacement 026 didn't work out. I think(hope) it just needs a new set of rings, but I still need to break it down and get a good look.

Long story short, after putting the PoulanPro back into service, it's been working pretty good. Everything feels about right, but it's lacking a bit of power compared to my echo cs400 which has similar specs. I was thinking a muffler mod might wake it up some.