MS280 muffler mod

I finally got around to modding the muffler on the 280. I'll snap some pics later. Basically I cut the flange off the back of the muffler where it locates itself into the exhaust of the jug. The area now entering the muffler was still a bit smaller than the actual port on the jug so I ground it a bit with a carbide. Then I removed the spark arrestor and 'adjusted' the size of the outlet to approx. 3x it's original size. Re-installed the arrestor and tached the saw. It wanted to run 15k!!! I added some fuel and brought it down to 14.5k, where it was obviously 4 stroking a bit. Made some cuts and the saw cuts great. Runs the exact same, but with more power everywhere. Little sucker screams now.

The plug shows the saw is pretty rich still. Is it safe to slowly ease it up to say 14.8k or 15k? Keeping an eye on the plug of course. With the way it is now it will 4 stroke pretty audibly in small wood like >3" or so. Only if you force it through will it run clean.

I'll try to snap some pics when I can.

I am gonna mod my 270 pretty soon. Let me know where you end up with it. 15k does sound a little high if the plug is nice, I'd run it.

Here's the pics. It appears as if I really need to extend the heat deflector.