661 Oil Test 32:1 vs 40:1 vs 50:1 ?

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cuttinties

cuttinties

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Im not following where we r suppose to think the piston is suppose to be perfectly clean on top without some depoists? Like I mentioned before the only way would be to use so much oil that it washes the depoists out but then u r getting tons of unburned fuel and oil out the muffler? Wouldnt it make more sense if u were getting a complete efficient burn from your fuel and oil at the right performance level that some depoists would have to eventually form on top of the piston?
This is what I look for. I concern myself with scavenging and proper tune more so than a little bit of carbon. A little bit of carbon coating in the exhaust port works as a insulator. A polished surface doesn't heat as fast, but it will hold heat longer. So for me I don't mind a little bit of a coating. The redundancy of this thread is insane.

8b7e142128528d3b3d33bc1967ec26fb.jpg
 
bwalker
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This is what I look for. I concern myself with scavenging and proper tune more so than a little bit of carbon. A little bit of carbon coating in the exhaust port works as a insulator. A polished surface doesn't heat as fast, but it will hold heat longer. So for me I don't mind a little bit of a coating. The redundancy of this thread is insane.

8b7e142128528d3b3d33bc1967ec26fb.jpg
Looks a little rich but is a decent example of what a piston should look like.
 
bwalker
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It's a strato saw that I ported that has run 40:1 Lucas. I told you about 65 pages back I'd get you a picture of a piston. Problem was that I didn't have time just to tear a saw down to take a picture.


Oh and it's m-tronic
That makes sense. Strato pistons look a little different. I have a Redman 8000 blower that looks almost identical after 5 years of daily commercial use in season and heavy home use there after for 7 years.
 
Moparmyway

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It's a strato saw that I ported that has run 40:1 Lucas. I told you about 65 pages back I'd get you a picture of a piston. Problem was that I didn't have time just to tear a saw down to take a picture.


Oh and it's m-tronic
I think it looks good !
Have any pictures of the rest of the piston ?
How much run time ?
 
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cuttinties

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That makes sense. Strato pistons look a little different. I have a Redman 8000 blower that looks almost identical after 5 years of daily commercial use in season and heavy home use there after for 7 years.
What I've found in my experience is that the better the scavenging process is the cleaner things will be. Making use of what's pumped through will limit carbon build up as there's less waste or excess. The less that's trapped in the squish area the better that's where chitty carbon comes from.
 
bwalker
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Fuel and air are compressed before combustion, most of the fuel burns in its liquid (atomized) state. You would have us to believe that most of the fuel is turned to a vapor, then combustion occurs; this is incorrect and where you are wrong.

Under heavier loads, the motor requires more fuel due to more of the atomized fuel flashing off into a vapor from the additional heat generated.

Atomized fuel in its liquid state provides combustion, fuel vapors burn at different rates and contribute very little to the power that atomized fuel produces.

http://inventors.about.com/library/inventors/blinternalcombustion.htm?utm_term=how a gasoline engine works&utm_content=p1-main-1-title&utm_medium=sem&utm_source=google&utm_campaign=adid-be29d3fc-99b1-4f9c-9f2c-bfb8ea8161f5-0-ab_gsb_ocode-4346&ad=semD&an=google_s&am=broad&q=how a gasoline engine works&dqi=&o=4346&l=sem&qsrc=999&askid=be29d3fc-99b1-4f9c-9f2c-bfb8ea8161f5-0-ab_gsb
Liquids don't combust until they change phase to vapor so you are completely wrong.
Given the above the rest of your assumptions are wrong as well.
 
Ron660

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Stihl 660 gas can.jpg
I would leave it in a metal can and mix only enough to use at one time. But really the same goes for any race fuel. You really don't want all those low boiling point components evaporating off. This isn't as big of a concern with pump gas due to changes in regards to evaporative emissions standards, but it still isn't a great idea to let your fuel get warm.
Already ahead of the game.
 
bwalker
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:omg:

Liquid fuel atomized (mixed with air) combust after ignition from the spark at the plug, this is not a diesel
Except by the time it reaches the combustion chamber it's largely not liquid as it has been evaporated by coming in contact with hot engine parts. Gasoline boils off at room temperature, so you really think it makes it to the combustion chamber in a liquid state? This change in phase is also what deposits oil on your bearings, cylinder wall, etc as liquid fuel/ oil mix doesn't have very good lubrication qualities...
 
Trx250r180

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:omg:

Liquid fuel atomized (mixed with air) combust after ignition from the spark at the plug, this is not a diesel

Here is a test ,throw a lit cigarette into a bucket of gas ,it will not light ,the liquid will not combust ,the fumes coming off the bucket of gas will though .I think this is the part he is trying to explain .The fumes are what burn .
 
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Here is a test ,throw a lit cigarette into a bucket of gas ,it will not light ,the liquid will not combust ,the fumes coming off the bucket of gas will though .I think this is the part he is trying to explain .The fumes are what burn .
Takes spark to light fuel. A cigarette doesn't have that.


Speaking of cigarette I think I'll have one.
 
bwalker
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Here is a test ,throw a lit cigarette into a bucket of gas ,it will not light ,the liquid will not combust ,the fumes coming off the bucket of gas will though .I think this is the part he is trying to explain .The fumes are what burn .
I don't know if I would try that as it just might ignite the vapors before it reaches the liquid fuel..
But one could certainly have a sparkplug submerged in fuel firing(if it didnt go to ground) and it would not ignite a damn thing.
 
cuttinties

cuttinties

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I don't know if I would try that as it just might ignite the vapors before it reaches the liquid fuel..
But one could certainly have a sparkplug submerged in fuel firing(if it didnt go to ground) and it would not ignite a damn thing.
I've won money doing the cigarette into gas off people who think like this.
 
bwalker
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Another example would be to use a spray bottle to spray diesel fuel on a lit candle. It would simply put the candle out.
The only difference in diesel fuel and gasoline is the temperatures in which their components boil off with diesel obviously boiling off at much higher temps.
 
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