Burnham
Woods walker
When they quit running right...otherwise, if it ain't broke don't fix it.
Idle speed and starting
- Thread starter Treeaddict
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Treeaddict
Treehouser
- Thread Starter Thread Starter
- #27
Will changing octane (89-91) or ethanol to non ethanol sometimes require tuning? I’ve ran all types of fuel without noticing any performance difference but I’m not a master. Only difference I’ve noticed is fumes are more harsh from pump gas vs the premix.
I want to open up the mufflers a bit on 3 saws so I suspect that will require tuning?
I want to open up the mufflers a bit on 3 saws so I suspect that will require tuning?
Magnus
TreeHouser
That is were setting after performance excels! If it runs at its best, perform correct it is most times the best setting with very few exceptions not worth mentioning
Nutball
TreeHouser
I hear that a lot, but don't believe it. The carb is a fixed fuel/air mixing device. Changes to the engine don't change the mixture. Slight changes to the mixture help get best performance at specific rpms. I think a muffler mod simply helps a person to hear if the saw is really tuned right to begin with or not. If anything, I would think there would be a benefit from leaning the carb after a muffler mod because the engine can rev faster, so it can benefit from a faster burning mixture, and a stronger pull on the carb may cause a richer mixture as the incoming air resistance increases putting a stronger pull on the fuel. In general I find saws run well on stock carb settings after modifications as long as the stock setting was correct to begin with.
Magnus
TreeHouser
Its all about timing, pressures, heat and flow in a engine. You need these things in right amount and if it runs hotter or colder than optimal it affects all things.
It all act and affect together. Change one thing, all is affected.
Setting saw after performance will show you that. Why make a muffler mod or any mod if there is no power gain?
Acceleration is good enough for most of us from scratch. In limbing is were you use it most and not many is limited by saw, rather limbing speed and technique.
Rpm is not always a good thing to increase, if what you what is chain speed so a pin up on rim is sometimes better if there is grunt in a saw.
The last 3000 rpm takes as long to get up to as it did to get to 10 000. So fast up to max power output point should not be at 13-15 thousand rpm. Takes time to increase high rpms. in High rpms the time allowed for pressures and flows are very narrow and not as accurate.
High rpm - less torque.
Low rpm's - less speed on cooling air if they are designed to run high with little load.
It all act and affect together. Change one thing, all is affected.
Setting saw after performance will show you that. Why make a muffler mod or any mod if there is no power gain?
Acceleration is good enough for most of us from scratch. In limbing is were you use it most and not many is limited by saw, rather limbing speed and technique.
Rpm is not always a good thing to increase, if what you what is chain speed so a pin up on rim is sometimes better if there is grunt in a saw.
The last 3000 rpm takes as long to get up to as it did to get to 10 000. So fast up to max power output point should not be at 13-15 thousand rpm. Takes time to increase high rpms. in High rpms the time allowed for pressures and flows are very narrow and not as accurate.
High rpm - less torque.
Low rpm's - less speed on cooling air if they are designed to run high with little load.
