Need help finding muff mod for Stihl MS310

After spending the day as a newbie and reading a bunch of threads, I have discovered that a muff mod might be a good idea.

So tonight I took off the stock muff...I have been told that muffs with cats cannot be modded but the ones without a cat can be....Is this true?

How do I know If I have a cat in mine? I cannot see any honeycomb looking pcs inside, because it is blocked by swiss cheese holes. When I shake it though, I can hear a block shaped deal in it, like a cat on a Harley, so I assume it has one.

So the questions are:

1. Can my stock muff be modded?
2. If not, which one do I need in order to mod it?
3. Once I have a moddable muff, can someone please point me in the direction of a thread with good info and pics on muff modding (since I am sure my search skills are laking and there is a thread on it already)?

Here is a pic of the stock muff, let me know if you need more pics, and what part you want a pic of.



Thanks in advance

Well, I posted this thread last night not realizing it might take a while to get admin approved.

Figured with the posting time, it might be a little far down the list so......bump...

Anybody help a newbie?

Thanks guys, and Happy Fathers Day to all the fellow dads out there..........

Welcome to AS!

Here's a link that might help you out: Muff mod how much is too much?

manyhobies said:

Welcome to AS!

Here's a link that might help you out: Muff mod how much is too much?

Click to expand...

:msp_thumbup:

that's definitely a good start, I like the spaghetti theory...

I may try and drill a few holes tonight, or head to the shop and really get carried away and mill a totally new muff from billet stainless.

manyhobies....thank you...rep for you

anyone else, feel free to pile on some more links and pics

Well, when I tried to reply last night, I got another admin must approve message, but when I reply via tapatalk, it seems to work.

My reply hasn't popped up yet, so I figured I'd reply with my phone

manyhobies said:

Welcome to AS!

Here's a link that might help you out: Muff mod how much is too much?

Click to expand...

Thanks manyhobies, this is a very goood start. The 85% rule seems logical and I really like the use of speghetti....





I did receive a pm with an email address, I was sent some pics and info and look forward to trying it this coming week.

Ill post up pics and my thoughts once the mod is done.

Thanks again, and Happy Fathers Day to all the fellow Dads out there.....

You should be able to enlarge the stock hole and refit the spark screen.You must readjust the carb richer or risk a melt down after opening up the muffler outlet.I had a MS310 awhile back and another member here put a stright pipe on it for me and it really uped the power output.

The best way to mod this is to remove the plate and screen. First two items on the muffler. The on the muffler right behind the plate, drill two-three holes in it. I'm going off memory but I think the holes are 1/4" or 5/16". Make sure you take the muffler off so you don't risk the shavings going into the cylinder. After that reistall the screen and plate. Once you get her running, make sure you adjust the H on the carb. Make sure it four stroking.

thats what i did to my old 310. i also connected the slotted holes at the bottom (i think they were in the bottom) and the thing sang a diff tune. i also trimmed back the deflector plate that deflects the exhaust gas 90deg at the output to make it more like 60deg or something.

my favorite ms310 muffrler mod is
step 1 set saw on stump
step 2 load buckshot into 12ga
step 3 take 10 paces back
step 4 take aim
step 5 fire


see mod done, best thing for a ms310:hmm3grin2orange:

Thanks for the responses, the guys who have suggested drilling multiple holes, is there a reason? Would just milling a largish rectangle hole in the indentation and enlargening the slots in the bottom work just as good? Or does it need differant holes?

Thanks again

tlandrum2002 said:

my favorite ms310 muffrler mod is
step 1 set saw on stump
step 2 load buckshot into 12ga
step 3 take 10 paces back
step 4 take aim
step 5 fire


see mod done, best thing for a ms310:hmm3grin2orange:

Click to expand...

Hmmmmm, I think this would add a few to many holes, and a few in the wrong place

Maybe you are just joking but if not, see below.....

Something wrong with a Stihl MS 310 other than its not your personal preference? I may be a newbe in this forum, but I am not new to forums in general.....why make a troll post in a reasonable thread?

Maybe just start and whole new thread about how you think Husky is better than Stihl, or that Fords are better than Chevy's or Glocks are better than XD's, its really a matter of preference?

That is all.....carry on...........enjoy your evening........

It's not a pro series saw. They are nice saws, a little tough to get into the cylinder and mods are pretty much limited to opening the muffler. Stock, they are a heavy for their weight. A muffler mod makes this ratio a little more acceptable. They don't handle as well because of the heft. The AV system is not as smooth as some. But all in all, they are a perfectly acceptable saw for lots of folks.

nmurph said:

It's not a pro series saw. They are nice saws, a little tough to get into the cylinder and mods are pretty much limited to opening the muffler. Stock, they are a heavy for their weight. A muffler mod makes this ratio a little more acceptable. They don't handle as well because of the heft. The AV system is not as smooth as some. But all in all, they are a perfectly acceptable saw for lots of folks.

Click to expand...

I can agree with this, as I have posted in another thread, I am not a professional logger, but when the need arises, a good running saw is nice to have. It is a little hefty especially since I hardly cut anything over 14 inches in diameter, but for the 60 bucks I paid for it from my neighbor who couldn't figure out why it wouldn't cut with the chain on backwards the first time he used it, I think it will be good.

nmurph, thanks again for your pm/email, your help was appreciated.

You open the muffler outlet area by 20% and four stroke the carb and sharpen the chain an go cut wood. I am of the mindset what a saw looks like or who makes is not as important as long as it does the job and gives me 120% effort :msp_thumbup:

HILLBILLYREDNEC said:

You open the muffler outlet area by 20% and four stroke the carb and sharpen the chain an go cut wood. I am of the mindset what a saw looks like or who makes is not as important as long as it does the job and gives me 120% effort :msp_thumbup:

Click to expand...

Quick and to the point, thank you......

What you are seeing is the "if it is not a 'pro' saw, it does not cut" bent of a lot of folks here. Every saw has to be the more expensive, probably more modifiable, even numbered(in the case of Stihl) saw.

The MS 310 works very well. I have used mine for about 12 years. It is still the saw I use when I am working a lot of 12 inch oak. It is certainly a saw that can give you years of service.

Welcome to the site. Watch out, CAD will get you sooner or later.

Hal

Wolfcsm said:

What you are seeing is the "if it is not a 'pro' saw, it does not cut" bent of a lot of folks here. Every saw has to be the more expensive, probably more modifiable, even numbered(in the case of Stihl) saw.

The MS 310 works very well. I have used mine for about 12 years. It is still the saw I use when I am working a lot of 12 inch oak. It is certainly a saw that can give you years of service.

Welcome to the site. Watch out, CAD will get you sooner or later.

Hal

Click to expand...

Ahhhhh, makes sense......

I do worry about CAD, I freguent a few gun forums and have fallen into addictions related to those as well, my most recent recovery is from EBR Disease (Evil Black Rifle i.e. AR-15).

Thanks for the post

xdmp22 said:

Ahhhhh, makes sense......

I do worry about CAD, I freguent a few gun forums and have fallen into addictions related to those as well, my most recent recovery is from EBR Disease (Evil Black Rifle i.e. AR-15).

Thanks for the post

Click to expand...

I am Hal and I suffer with CAD.

I started with one saw - a MAC 610. Now there are 8.

Hal

Just remember these series of saw are NOT pro series. They are homeowner series. Many guys don't like them because they are a pain to work on. They are a bit more complicated to get the cylinder off. Not as easy as the pro series. I have a 290 that I have ran for 10 years and the only issue is it was straight gased. Long story on that. The saw didn't fail because it mechanical failed it didn't last because of operator error. Any ways. IIRC, if you drill too many holes on the muffler you will need to adjust to carb (H side) too many turns out and you will not receive a good throttle response. It will start to bog down then pickup when you blip the throttle. Hope this makes sense. Start small and then adjust until you like it.

tlandrum2002 said:

my favorite ms310 muffrler mod is
step 1 set saw on stump
step 2 load buckshot into 12ga
step 3 take 10 paces back
step 4 take aim
step 5 fire


see mod done, best thing for a ms310:hmm3grin2orange:

Click to expand...

Best take 2 shots to make sure.