What oil is best? and what ratio?

[Deets066]

here is theory saws that use oil that have a lower viscosity and flash point will make better power than other oils that have a higher viscosity and flash point. as the oil that is burning with the gasoline will produce more BTU's than the other other that is not being burnt and left behind in the engine.
that is the way my little pea size brain understands this.

That's one way to look at it.

I look at it as a "good" oil will have more viscosity will have less piston and bearing wear. It will also provide a better seal with the rings, which means more compression and no blow by.

Less viscosity cheaper oil with lower flash point may burn hotter but may have some blow by. Black carbon burnt past the rings. Which means your not burning all the fuel you transferred from the case

 

[Keith Gandy]

Perfect !!View attachment 19513

Cant tell what that is really well Kevin? Piston?

 

[Deets066]

Cant tell what that is really well Kevin? Piston?

Yup, piston crown from a bore scope

 

[Keith Gandy]

Yup, piston crown from a bore scope

Ok. Couldnt tell well. Looks like a popup. Is that ran on his r50/800t mixture at 25to1 with vp94? How much run time and is it with the wj69 and tuned to what?

 

[Deets066]

Yes on the fuel and oil, I think he was tuned around 13,800. Not sure how much run time

 

[Keith Gandy]

Yes on the fuel and oil, I think he was tuned around 13,800. Not sure how much run time

Sure is clean

 

[Keith Gandy]

Heres a question I have wondered about. Does a clean piston top offer an advantage over one with carbon on top? Does carbon on top of the piston keep the piston from absorbing as much heat or does the piston need to absorb the heat to transfer it to the cylinder and fins?

 

[Moparmyway]

Its my 661 after running about a dozen tanks of my 50/50 mix (R50 & 800) with VP 94 SEF @ 25:1 with the WJ69 and standard coil tuned to 13,750

The squish is just about spotless except for a shadow on each side of the exhaust port

The crown is all carbon except slight transferr wash

According to some theories floating around, the excess Oil at 25:1 should have kept the crown spotless.

I've learned alot from Ben, Mike, and Jason ......... I'll just stick with my "exotic" non ethanol fuel and see how the different Klotz oils perform and smell.

 

[Moparmyway]

Less viscosity cheaper oil with lower flash point may burn hotter but may have some blow by. Black carbon burnt past the rings. Which means your not burning all the fuel you transferred from the case

Heres a question I have wondered about. Does a clean piston top offer an advantage over one with carbon on top?

IMHO, rings are where dudes need to be concerned. If there is carbon in the rings or lands, you've got to address something. Carbon in the chamber and on the crown is what's necessary for good combustion

 

[Deets066]

wonder why you quoted Keith's post and it says it was from me?

 

[sawmikaze]

wonder why you quoted Keith's post and it says it was from me?

Voodoo

 

[Keith Gandy]

Its my 661 after running about a dozen tanks of my 50/50 mix (R50 & 800) with VP 94 SEF @ 25:1 with the WJ69 and standard coil tuned to 13,750

The squish is just about spotless except for a shadow on each side of the exhaust port

The crown is all carbon except slight transferr wash

According to some theories floating around, the excess Oil at 25:1 should have kept the crown spotless.

I've learned alot from Ben, Mike, and Jason ......... I'll just stick with my "exotic" non ethanol fuel and see how the different Klotz oils perform and smell.

Kevin I cant tell if the piston has carbon or not? Is the top all carbon except wash marks?

 

[Moparmyway]

wonder why you quoted Keith's post and it says it was from me?

That was not intentional, I'll see if I can fix it

Kevin I cant tell if the piston has carbon or not? Is the top all carbon except wash marks?

All carbon except squish and slight wash marks

 

[Keith Gandy]

800t with 87 efree at 32to1 in a ported 461 tuned to 14600 to 14800 loaded with a 28" bar. Looks to be combusting but there was more carbon but I wiped it before the picture as some came off

 

[Keith Gandy]

That was not intentional, I'll see if I can fix it


All carbon except squish and slight wash marks

Kevin I wonder why the wash marks close up if u go back to pump gas?

 

[Keith Gandy]

I believe the lower octane will produce less wash marks. I dont know that for sure but I switched to 93 efree and alil techron in my mix and ill compare to the pics in my hybrid with 87efree

 

[Ron660]

Ok question here ,a hopped up bad ass chainsaw that scares women and children when it is started may have 230 psi for example ,i bet it still does not have more than 8 to 1 compresion which 87 octane would be fine for ,the 110 race cas burns too cool making wasted fuel not being made into energy out the exhaust kind of like some bike oils are doing in the saws. The saws just do not have enough power nor generate enough heat to benefit from these fancy fuels and oils ????

Only way to know is compare different octanes in your saw with timed cuts.

 

[Ron660]

Brian some dont understand the top and bottom capacities that r measured to derive the ratio r different in a saw compared to a vehicle with high psi. U cant use a baseline chart for a octane/psi chart for a car to compare to a saw not knowing your ratio and assuming it? I think it would be easy for someone to pull a octane/psi chart for a vehicle off the internet with 14to1 compression ratio to a saw @8to1 the chart wouldnt apply to a saw? And the chart surely doesnt work if u havent measured your ratio and guess? These work saws have too short of a stroke to have time to detonate and have any benefit from high octane

It's very simple. Test your ported saws with different octanes and that's your answer. Your mtronic saw was faster with higher octanes the same as mine was. Theorizing isn't going solve anything. Timed tests will.

 

[Ron660]

That's one way to look at it.

I look at it as a "good" oil will have more viscosity will have less piston and bearing wear. It will also provide a better seal with the rings, which means more compression and no blow by.

Less viscosity cheaper oil with lower flash point may burn hotter but may have some blow by. Black carbon burnt past the rings. Which means your not burning all the fuel you transferred from the case

I've seen a few pics of Klotz which black carbon on the piston past the rings.

 

[Keith Gandy]

Only way to know is compare different octanes in your saw with timed cuts.

The timed cuts isnt whats on my mind right now as much as the quality of the fuel and how does octane effect cleanliness and wash patterns