Building work 441

[Wild Knight]

I want to mod my 441 to make it a little better work saw. I'd like to increase the torque, while minimizing the change in fuel consumption.

I know the basic mods consist of opening the muffler, porting, polishing, lightening the piston, raising compression (either pop-up or lowering the jug). I have read that the muffler mod produces the most gains. While porting and polishing takes the most time, it yields the least gains per effort unless you really take away some metal. All of these mods come at the expense of extra fuel though. I'm told raising the compression is great for building torque and doesn't hurt fuel consumption. Don't know how much gain there would be by lightening the piston.

What would be the priority list of steps for building a work saw (more power, minimum increase in fuel consumption)? I am kinda thinking it may go something like this:

1) raise compression (lower jug, pop-up, still use a gasket)
2) muffler mod (50-60% bigger)
3) polish (remove casting marks, make smooth)
4) port (5-10% wider)
5) lighten the piston

 

[Brownpot Deaton]

order sounds reasonable for not using up fuel combined with grinding, but fuel is also where the realhp is, and thte biggest hp gain in my mind is porting...i say do it step by step trying it out each time and stop when u like it if your that woorried about fuel....

 

[Wild Knight]

I'm not unhappy with the power it produces right now, but I like making things better I think efficiency in most things can always be increased. There has to be 'free' power in there somewhere that can be harnessed.

I don't want to max out the saw; not looking for big HP gains. I just want it to hold its torque better when I lean on it, as well as with bigger bars in big wood.

 

[smokinj]

I want to mod my 441 to make it a little better work saw. I'd like to increase the torque, while minimizing the change in fuel consumption.

I know the basic mods consist of opening the muffler, porting, polishing, lightening the piston, raising compression (either pop-up or lowering the jug). I have read that the muffler mod produces the most gains. While porting and polishing takes the most time, it yields the least gains per effort unless you really take away some metal. All of these mods come at the expense of extra fuel though. I'm told raising the compression is great for building torque and doesn't hurt fuel consumption. Don't know how much gain there would be by lightening the piston.

What would be the priority list of steps for building a work saw (more power, minimum increase in fuel consumption)? I am kinda thinking it may go something like this:

1) raise compression (lower jug, pop-up, still use a gasket)
2) muffler mod (50-60% bigger)
3) polish (remove casting marks, make smooth)
4) port (5-10% wider)
5) lighten the piston

sounds like #1 and #2 going to be very happy with it simple seems to be better if your working with it every day this should use any more fuel.

 

[Erick]

I want to mod my 441 to make it a little better work saw. I'd like to increase the torque, while minimizing the change in fuel consumption.

I know the basic mods consist of opening the muffler, porting, polishing, lightening the piston, raising compression (either pop-up or lowering the jug). I have read that the muffler mod produces the most gains. While porting and polishing takes the most time, it yields the least gains per effort unless you really take away some metal. All of these mods come at the expense of extra fuel though. I'm told raising the compression is great for building torque and doesn't hurt fuel consumption. Don't know how much gain there would be by lightening the piston.

What would be the priority list of steps for building a work saw (more power, minimum increase in fuel consumption)? I am kinda thinking it may go something like this:

1) raise compression (lower jug, pop-up, still use a gasket)
2) muffler mod (50-60% bigger)
3) polish (remove casting marks, make smooth)
4) port (5-10% wider)
5) lighten the piston

Law of energy conservation says "Energy can not be created or destroyed"... in other words if you want more energy (HP) out of the saw you will have to put more energy (Fuel) into the saw. Yes I'm sure there are some potential efficiency gains to be made but you have to remember that everything comes at a cost.

1) raise compression (lower jug, pop-up, still use a gasket)

Raising compression will increase efficiency and produce more power but at the cost of heat and an increase in temperature.

2) muffler mod (50-60% bigger)

The muff mod will help to remove some of the heat from the increase in compression and will in and of it's self help to increase power but at the cost of fuel consumption.

3) polish (remove casting marks, make smooth)

Always a good idea.. anywhere you can smooth the transition and create better flow is gonna be a good thing. This may be the only "free" power you find in the saw and it will be minimal at best.

4) port (5-10% wider)

Wider is typically better but there again at the expense of fuel consumption.

5) lighten the piston

See #3.... the amount of material you would have to remove to make a significant difference would very likely weaken the piston structurally. Fine in a race saw where every tenth of a second counts and it only has to run for five seconds at a time, but it's a small piece of the larger pie. Smooth the casting lines and rough transitions to help promote good flow and let it ride.


Bottom line is when you decide to modd a saw you have to figure out what you need/want it to do and what you're willing to sacrifice to get it. You have to decide what the perfect balance is for your personal comfort level and the saw you're building..... the factory engineers have already given you their opinion on the matter.

 

[2000ssm6]

To add to what the others said, you are going to give up fuel mileage when geting more power. However, having ported 044s/440s and 460s and knowing they drink gas like a fish does water. The 441 should stihl have an advantage over them using less fuel, even ported. My 441 is only muffler modded so far, but will be ported later. The 441 sips fuel when compared to it's older brothers.

 

[CanadianCarGuy]

From my experience with the 441, take your die grinder and stick that rasp as far up those skinny little slits for transfers and widen them, then be careful on the intake port only a small window to work with, raise it a little and widen it a little. Then the other two passages in the intake can be straightened out and widened. Machine the cylinder down a little, sandpaper works for this if you have patience and check the squish for even number all the way around. Then widen the exhaust, cut the muffler in half, cut that snorkel of a baffle out, weld muffler back together and another port. Remove limiter caps from carb, grind the key slot out of the flywheel, advance timing 12 degrees to 16 degrees. Then you will have a 441 that eats 460s at least stock ones. Also watch out for the throttle cable coming out, it made me think I had an air leak and I must tore the saw apart 4 or 5 times trying to see if I have screwed something up with my porting.

 

[CHEVYTOWN13]

Also watch out for the throttle cable coming out, it made me think I had an air leak and I must tore the saw apart 4 or 5 times trying to see if I have screwed something up with my porting.

I agree, watch out for a snag on the throttle cable. That happened to me on the 5100 while I was switching carbs and got the throttle cable snagged. I also thought it was an air leak. It was revving so high and at one point I forgot I had the chain break engaged. It happened so fast, but smoke started to come out of the clutch cover like nobody's business:jawdrop:

 

[Meadow Beaver]

I agree, watch out for a snag on the throttle cable. That happened to me on the 5100 while I was switching carbs and got the throttle cable snagged. I also thought it was an air leak. It was revving so high and at one point I forgot I had the chain break engaged. It happened so fast, but smoke started to come out of the clutch cover like nobody's business:jawdrop:

I had my 044 (which had a short life) over rev @ about 20k and detonate.

With your 441 if you want it to be torquey you can mill it 25/25 or 30/30. Then when you have the pop-up it will make some nice compression.

 

[CanadianCarGuy]

Here is a vid of my 441. The throttle response is quicker than i expected, but the torque is not as much as I was hoping for, but I did leave a lot on the table as I didn't mill the cylinder, mess with squish, or do a pop-up piston. The piston was not touched either, I can see a lot of mass can be removed here, but I didn't want to mess with too much as this was the first stratocharged saw I ported. I am pushing pretty hard, as this chain was the wrong one, I grabbed the dull one off the grinder instead of the one I had just ground by mistake. Also an 8 pin sprocket on the saw. There is not a lot of widening available on the intake, but I did raise it significantly. I don't do port timing numbers so no information available on port timing numbers. What do you guys think? Potential or no? The first vid is stock the second is ported. I also forgot that there is no baffle in the 441 muffler, I got it confused with the 361!!!

http://www.youtube.com/watch?v=q_MT4Gu5Gx4

http://www.youtube.com/watch?v=AW0g_XKKzhA