Mastermind Meets The MS661 C-M

[CR500]

Randy I will be in touch if this is true... you have been a big help to me understanding saw tweaking techniques.

 

[Buffhunter]

I just want everyone to know that I'm done here on AS. Claudio and I can see eye to eye. He can keep the place......I'm out.

SERIOUSLY WTF JUST HAPPENED? ????

 

[Chris-PA]

I suspect the reason you saw limited gains is that you employed your usual strategy, which is a good one and the same one that the Stihl engineers used - so limited gains in that direction.

This thing meets emissions limits without strato. The usual approach used there seems to be:

• Short exhaust duration to keep cylinder pressure up
• Carefully designed quad high velocity transfers & reduced case volume to reduce scavenging losses

Usually they stick a cat on to deal with the terrible fuel mixture control of traditional carbs, but I guess with M-tronic they avoided that.

Then again I could be all wrong.

Having just returned after 6 months I'm sorry to see you go. I hate You-tube and rarely watch videos so I won't see your work anymore, but then I'm not a target audience anyway. Good luck.

 

[treesmith]

Looks like they shot themselves in the foot, this place will be poorer without you, Randy. Thanks for everything and I'll be in touch, I've heard you can do good things with chainsaws.......

 

[Mastermind]

LMAO....

One Monkey don't stop the show.

 

[Trx250r180]

LMAO....

One Monkey don't stop the show.

No............it will just be playing in another theater .................

 

[splitpost]

Thats too bad,have seen alot of guys leave AS Since joining in 2009
guess i will just catch him on a different channel from now on

 

[MCW]

hey Randy, what if you just put a hole in the center of the front muffler cover and then put spark arrestor screen over it. Kinda like the 660 setup. Wouldn't the exhaust venting straight out be the easiest quickest path?

It's also the quickest path for setting the log you are cutting on fire These types of muffler mods look cool but in real world cutting they are actually potentially dangerous. In larger logs during extended cuts you'll need a fire extinguisher handy.

 

[bootboy]

It's also the quickest path for setting the log you are cutting on fire These types of muffler mods look cool but in real world cutting they are actually potentially dangerous. In larger logs during extended cuts you'll need a fire extinguisher handy.

I've got just such a muffler on my 460 and have never started a fire. In cuts where I have my 30" bar buried, I've charred bark but never gotten embers. The pipes go into my muffler at angles and so the exhaust circulates a little before coming out. It also helps to maintain a little more pressure in the muffler without restricting it.

 

[singinwoodwackr]

It's also the quickest path for setting the log you are cutting on fire These types of muffler mods look cool but in real world cutting they are actually potentially dangerous. In larger logs during extended cuts you'll need a fire extinguisher handy.

even the side discharge can ignite a log covered with dry moss...done that

 

[MCW]

I've got just such a muffler on my 460 and have never started a fire. In cuts where I have my 30" bar buried, I've charred bark but never gotten embers. The pipes go into my muffler at angles and so the exhaust circulates a little before coming out. It also helps to maintain a little more pressure in the muffler without restricting it.

Just because you haven't done it doesn't mean it can't happen. As mentioned above it can and does happen. If you got caught with such a modification in an Australian forest you'd be kicked straight out and possibly even fined. I've caught bark alight plenty of times on certain tree species. I played around with straight through muffler mods for a bit of fun on 365's with BB kits and canned them pretty quickly before I started a bushfire. I never noticed any power increase over a standard muffler mod and I doubt any of the builders here have noticed a difference in power either.

 

[The Ripper]

The only differences I "HEAR" is a louder exhaust pulse along with the power distribution being somewhat broader.

 

[bootboy]

Just because you haven't done it doesn't mean it can't happen. As mentioned above it can and does happen. If you got caught with such a modification in an Australian forest you'd be kicked straight out and possibly even fined. I've caught bark alight plenty of times on certain tree species. I played around with straight through muffler mods for a bit of fun on 365's with BB kits and canned them pretty quickly before I started a bushfire. I never noticed any power increase over a standard muffler mod and I doubt any of the builders here have noticed a difference in power either.

Well, good to know if I ever travel to Oz with my saw. Most of my work involves yard trees so I'm not particularly concerned. I have a stock front cover that I can change out but it requires re tuning and losing a noticeable amount of grunt... and noise.

 

[MCW]

Well, good to know if I ever travel to Oz with my saw. Most of my work involves yard trees so I'm not particularly concerned. I have a stock front cover that I can change out but it requires re tuning and losing a noticeable amount of grunt... and noise.

I wasn't trying to be a smartarse with my comment but just stating a few observations over many years of using saws under many conditions from dry arid areas to basically rainforest. Potential fire risks are certainly not an issue in rainforests. Yard trees aren't really an issue with starting fires but I'm pretty certain that areas of US forestry would have the same concerns as Australia.
Some of the muffler modifications I've seen on AS over the years are quite laughable and similar to that 17 year old kid putting a 5" exhaust on his stock Honda Civic. Sound alone would make him think he's gained 50HP

 

[MCW]

The only differences I "HEAR" is a louder exhaust pulse along with the power distribution being somewhat broader.

The power increase and broader power distribution is a result of modifying the muffler full stop, not as result of having a front exit. Adding an extra side port will have exactly the same results.

 

[shootingarts]

I wasn't trying to be a smartarse with my comment but just stating a few observations over many years of using saws under many conditions from dry arid areas to basically rainforest. Potential fire risks are cetainly not an issue in rainforests. Yard trees aren't really an issue with starting fires but I'm pretty certain that areas of US forestry would have the same concerns as Australia.
Some of the muffler modifications I've seen on AS over the years are quite laughable and similar to that 17 year old kid putting a 5" exhaust on his stock Honda Civic. Sound alone would make him think he's gained 50HP

Kids today don't know nuth'n! Everybody dry behind the ears knows to get fifty horsepower from exhaust mods on a car you gotta go to dual pipes with Hollywood Glasspaks. Get them good and hot and then run a few gallons of water from the garden hose into each exhaust pipe to blow most of the glass out. Then you got a runner!!

Got an exhaust idea I want to try on a saw, based loosely off of an old circle track racing muffler. Don't know if they are still marketed or not. If the idea works it would be dead simple to tune exhaust.

Hu

 

[singinwoodwackr]

Kids today don't know nuth'n! Everybody dry behind the ears knows to get fifty horsepower from exhaust mods on a car you gotta go to dual pipes with Hollywood Glasspaks. Get them good and hot and then run a few gallons of water from the garden hose into each exhaust pipe to blow most of the glass out. Then you got a runner!!

Got an exhaust idea I want to try on a saw, based loosely off of an old circle track racing muffler. Don't know if they are still marketed or not. If the idea works it would be dead simple to tune exhaust.

Hu

I've always assumed that stickers are the key to massive HP.

 

[gmax]

The power increase and broader power distribution is a result of modifying the muffler full stop, not as result of having a front exit. Adding an extra side port will have exactly the same results.

Now you tell me

 

[MCW]

Now you tell me
View attachment 325139

Heh heh. Sadly I have seen muffler mods like that on AS that were serious!

 

[windthrown]

I wasn't trying to be a smartarse with my comment but just stating a few observations over many years of using saws under many conditions from dry arid areas to basically rainforest. Potential fire risks are cetainly not an issue in rainforests. Yard trees aren't really an issue with starting fires but I'm pretty certain that areas of US forestry would have the same concerns as Australia.

I am with the Aussies on this one. If you get caught with a saw w/o a spark arrester here in fire season it is a large fat fine. Muffler mods they do not care much about, but the spark screens, we have to have them here. Also if you start a fire here, you are liable for any and all damage done by it, and you may also be liable for the cost to put it out. Spark screen or no spark screen, we also have restricted cutting hours in summer months here that vary through the season. Semi-hoot owl, and hoot owl restrictions, as they are called. No cutting during the heat of the day, and you have to have at least some fire suppression equipment.