First MS440 Mod/Squish Question

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magicmanar98

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I bought a used MS440 a couple months ago. Never even started it up. I was planning on taking plastics off and just cleaning it up. Well, it didn’t quite work out that way. I tore it all the way down short of splitting the case. Bearings were still good. I decided to try a port and polish job which led to lots and lots of reading. I widened intake and exhaust and smoothed them out nicely. My noobism gave me little leeway to work on transfers so I just cleaned out imperfections and widened a touch. I have this dremel wheel that is basically a scotch Brite pad and put a nice cross hatch on smooth bore. Put a new set of rings, oil seals, and cylinder gasket delete. Dual port muffler with a bit of opening up on the inside. Advanced timing by about a third of the woodruff key. New adjustable walbro hd15 in place of the hd17. Time to pull the rope. Didn’t have my hopes too high but holy crap this dude took off. A bit of carb adjusting and this is one impressive machine! It lopes like a dragster and throttle response is amazing. The only thing I’m upset about is that I didn’t take pictures throughout the build. I am hooked folks.
 
On to the squish. I’ve pretty much gathered from reading is that you want a minimum of .020 squish. Well, I am a fuzz under. Using the solder method and averages squish is right at .017 - .018. I didn’t hear anything that sounded like danger but I didn’t get into hard or put it deep in the wood. Am I gonna blow this thing up or am I just short of the critical zone? What do you all think? Anybody run their saw in this squish range? Thanks for any input.
 
.017" squish is entirely fine on that saw.

I had mostly .018’s but did have a few .017’s out of 10-12 tests. I also used digital calipers for the measurements. I may grab a micrometer from work and see what I get.
 
I could just start this saw and listen to it idle. I’ve never heard anything like it from a chainsaw. It sounds like I put a high lift cam in it.
 
The next “scientific” project I’ll be doing is a total aftermarket MS440 build. Will have OEM Crank, bearings, and seals. Farmertec crankcase and smalls. Highway 52mm cylinder and some sort of pop up piston. Can’t remember brand. Gonna put it together without any cylinder mods. Basically stock except big bore and compare to last build. Then I’ll do the porting and so on and see how that matches up. This is gonna be fun.
 
Be careful it's an addiction. I just bought a lathe for my addiction and looking at a couple of different angle head tools.
 
I wouldn't be afraid to run it like I hate it with that squish.
Hell I've got to wear I dont even check when yanking a base gasket.
 
Be careful it's an addiction. I just bought a lathe for my addiction and looking at a couple of different angle head tools.

It is quite an addiction. But I love it and there’s no better feeling than hearing that first pop when it’s time to yank on the starter. Plus, I’m tired of my wife getting to spend all the money. If it’s not there she can’t spend it. So in theory, I’m helping cure her addiction of spending money
 
I wouldn't be afraid to run it like I hate it with that squish.
Hell I've got to wear I dont even check when yanking a base gasket.

True, if it blows up that’s just an opportunity to do it again
 
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