mods MS 170

[thekid95]

hey look ive gotta MS 170 that i use to cut firewood and i was wonderin is there anything i could do to it to make it have a little more oomph
is thier anyone that could maybe help me?

 

[Bubbles Up]

Have a look in the regular chainsaw forum,do a search there is a muffler mod that can be done , just make sure that you re-tune the carb, you will need,to have the Low/H[igh/B]/LAidle screw.If you wanna get wild do a full porting job search on that too.

HTH

 

[rickyrooster]

do a search in the chainsaw section. I think there is a piece on putting a fully ajustable 025 carb. in a 018 stihl. then you will be able to mod the muffler and retune it. You can also buy a 018 cylinder and piston. it is a direct bolt in and is good for about 20% more power than your stock 017 is.

 

[Artsi_L]

I've gotta Stihl 180. Too bad the carb is self adjusting, so no tinkering screws anywhere. It's been working allright in stock shape, but lack of screws worries me if I do any port job on it.

I timed the ports several times over on this 180. The stock timing sets new standards for word "conservative". I did check and recheck for errors in timing. None that I can find. Figures are here:

EXH. DUR. 140º
TRANSFER DUR. 96º
BLOW DOWN 22º

Local Stihl dealer told me the unloaded max rpm for 180 model is 15 000rpm, and cutting is at 10 000rpm.
I'm surprised the thing can actually cut at 10 000rpm with those timings.

I guess I'll try straight on with a pipe before anything else. I'm hoping that'll give some more oomph.
Theory behind this approach is that I'm dumping precious air/fuel mixture straight outta exhaust. Having design pipe to take care of that, my cylinder's volumetric efficiency should get better, hence more power with somewhat same fuel consumption (and I most likely don't have to worry about readjusting the carb, which cannot be readjusted anyways).

I have bought a 2-stroke pipe design software. That makes design job for the pipe a piece of cake.

 

[brokenbudget]

best mod you can do is trade it in on a bigger saw.

 

[ncfarmboy]

I did the 021-025 adjustable carb change on a 180 same saw as 170 but bigger cyl. Pretty easy with minor mods. Use air horn from old carb on 021-025 or plug the hole in the air filter housing.. Zama to Zama Walbro to Walbro. I ran into this when I did mine check to see which carb. you have before buying adj. carb. Really helps this saw. Read about using 021-025 air filter setup on this mod. Doesn't work too well. Have to severely modify cyl. cover and fab some kind if holdown because cover lock doesn't line up. Spent $30 to find this out. If you change carb stay with original air filter setup. However it's worth it to have adjustable carb.

Shep

 

[treesmith]

I've got a ms170GTi that lives to feed the chipper, has a 12" .043 chain and cuts like a demon, has a 12" picco duro carbide chain if things get dirty. I bought it early last year or maybe end of 2011. The walbro 215 from 025 (fleabay) fits on with little trouble. There's a thread on here for the ms 180 and they're virtually identical. The air filter housing already has holes for carb adj screws, you just need to line them up with the outer casing and drill through and also put a new hole in for tickover screw which is in a different spot, that needed to go through the handle too. Open up the muffler and you're away, more poke and throttle response. I've heard its a bad idea to open the exhaust without being able to richen the mix.

It takes everything I throw at and drop on it and its so reliable, light and easy to use. When it dies the carb will come off and I'll do it again. It cost $300 Aus new and stops me using my 200 so I can't see the downside