I call B.S. on Stihl. My dyno doesn't lie. MS 461 is king over MS 660

[Mastermind]

Randy... how much gain do you see from a 660 after porting?

The difference is huge.

Most of the gain comes from the machine work though.

The lower I can get the exhaust the better, but there is a point that the bottom of the piston skirt begins to go up into the exhaust port, AKA free porting.

I take .060" from the squish band. That gets my exhaust duration down, adds intake duration, and raises compression in one step. Then the upper transfers are "massaged" extensively.

 

[walexa07]

Stihl Australia shows 7.1 bhp and Stihl USA shows 7.0 bhp. Are Australia hp numbers reflecting a dp muffler? If so, would that only be good for .1 bhp? I can easily believe Stihl publishing hp data based on the max they can get with factory equipment, whether more restrictive equipment is required or not.

I do believe the 660 is capable of more power than the 461, just on the basis of "there's no replacement for displacement", and it's a more durable chassis no doubt. It's just interesting that the EPA has pushed them to detune this saw so much.

Waylan

 

[Trx250r180]

Depends what you use the saw for ,the 660 was not built for cutting 12 inch cookies ,it was made for a bigger bar falling timber,look at the clutch alone or the bigger bearings ,if i mill with the 460 or 461 the clutch drum will turn blue ,the 660 it does not ,yes the both have similar power and do the job ,but i do not think the smaller saw will hold up like a 660 long term if put to use in place where a bigger saw should be

 

[Mastermind]

Well said Brian.

 

[Gologit]

Depends what you use the saw for ,the 660 was not built for cutting 12 inch cookies ,it was made for a bigger bar falling timber,look at the clutch alone or the bigger bearings ,if i mill with the 460 or 461 the clutch drum will turn blue ,the 660 it does not ,yes the both have similar power and do the job ,but i do not think the smaller saw will hold up like a 660 long term if put to use in place where a bigger saw should be

Exactly right. I like my 461 but if I'm into big timber on an every day basis I want a bigger saw.

All this cookie cutting stuff and number juggling is fine and I'm sure the motor heads are having fun with it. It doesn't really address the main issue though.

The 461 is a fine little saw and yes you can run a 32 or 36" bar on it. But if you do, and you work the snot out of it all day every day, will it last as long as it's big brother? I don't think so.

 

[redfin]

Randy... how much gain do you see from a 660 after porting?

I was very much dissapointed with my stock 660 until Randy played with it. Even with a 25 in oak my 044 would keep up with it.

 

[Mastermind]

What a lot of you guys are missing is this. The 660 doesn't really shine until the wood gets big. Like Bob and Brian both said, the saw is tough in large timber, or for milling.

Does it need to be ported to be a serious runner? Hell yes.

 

[chadihman]

So what rpm does a stock 660 run at in big wood or milling? I fully agree that the 660 has more torque but this particular one only had more torque below 7500 rpms. Im not saying they all do and I'm also speaking of a U.S. stock 660.

 

[Mastermind]

I'm not saying it will have more power...........just that it will live longer than a 461 in big stuff.

 

[chadihman]

What a lot of you guys are missing is this. The 660 doesn't really shine until the wood gets big. Like Bob and Brian both said, the saw is tough in large timber, or for milling.
Does it need to be ported to be a serious runner? Hell yes.

Not this 660 unless they often hang in 7000 rpm or lower range. Maybe I have a cherry 461 but the 660 is supposed to be 1 HP more. That's a big jump.

 

[Mastermind]

What you are saying is that the 660 is even, or so, with the 461.

Stihl says that it should be one full HP more powerful though.

Right?

I am not at all surprised.

 

[Brush Ape]

The 461 is a fine little saw and yes you can run a 32 or 36" bar on it. But if you do, and you work the snot out of it all day every day, will it last as long as it's big brother? I don't think so.

They are comparing the MS461 to a MS660 here. Them two saws are barely cousins.

 

[chadihman]

What you are saying is that the 660 is even, or so, with the 461.

Stihl says that it should be one full HP more powerful though.

Right?

I am not at all surprised.

You didn't read my first post in thus thread did you?. Its OK I do the same thing all the time.
I'll fill you in. The 660 is supposed to be 1 HP stronger than the 461. I broke the brand new 660 in on the dyno with a little over two tanks then tested both stock saws back to back twice on the dyno from 10,000 all the way down to 6500 rpms. I recorded #s every 500 rpms. The 461 was 2-3% stronger at 10,000, 9500, 9000, 8500, and 8000 rpms. Then at 7500 they were tied. Then the 660 was 3% stronger from 7000-6500 rpms.

 

[Mastermind]

Yeah I read your first post......that's what I just said.

The 461 and the 660 are ever......or so.

But Stihl says the 660 is suppose to be 1 HP stronger.

 

[Mastermind]

I broke it down for the Brush Ape.

 

[Trx250r180]

So what rpm does a stock 660 run at in big wood or milling? I fully agree that the 660 has more torque but this particular one only had more torque below 7500 rpms. Im not saying they all do and I'm also speaking of a U.S. stock 660.

I have not put a tach on my saw milling ,i will note when the jug was stock i used all the throttle in a pass ,only mod was a dual cover and stock opening opened up some ,Randy ported it where he thought it would work good for milling ,now the power has more pull ,and in a pass i only need to use about 2/3 throttle now and it chugs right through real smooth with a 28 inch bar ,if i hold it wide open sounds like it is spooling up too high with this bar ,am sure when i throw a 42 on it ,i will need the rest of the throttle ,nice to know i have extra power to spare now i may get one of those little tachs and zip tie it on see what it reads some time ,am kind of curious now
Yes i have been told saws need to run at wide open throttle in a pass ,i have pulled my muffler cover and checked my plug ,it gets plenty of fuel doing the way i do ,inside the can is oily still

 

[Mastermind]

I would slow it down with more fuel Brian. Part throttle scares me.

 

[Brush Ape]

But Stihl says the 660 is suppose to be 1 HP stronger.

It is at 9500 RPM.

 

[treesmith]

Can't remember if I've posted this before but anyway, this was the second job for my Mastermind 660 and the first time it wore the 36", believe it or not this tree was planted by the homeowner and only 42 years old, roughly identified as a type of blue gum and rock solid. We used a stock 395 too. I don't think a 461 would have managed it, certainly no where near as well.

 

[mdavlee]

The last 660 I ported ran around 10k in the wood milling about 22" wide. I didn't have to push hard on it with the chain set up. I haven't tached the 046 in the wood milling so I can't compare. I d get more bd ft milled per fuel with the 088 over a 660 or 390.