Chainsaw Dyno broke down. Tired of spending $ off to the scrap pile it goes

[old-cat]

Research and development does things that are WAY out of the ordinary! In the book they were not using production engines. It's all about TESTING and pushing the limits. They do things that common folk can't even imagine.

 

[dozerdan]

Research and development does things that are WAY out of the ordinary! In the book they were not using production engines. It's all about TESTING and pushing the limits. They do things that common folk can't even imagine.

OK they didnt use production engines for the testing. I would still like to know what compression ratio was tested.
I would like to see some testing with the gasoline that we have available today not what they had in 1928.

Later
Dan

 

[old-cat]

I don't have the book and it was many years ago. They used a variable compression engine and I believe 11:1 was the highest they tested.
They had a very long in-depth chapter about fuels and I assure you there is nothing we have today that they weren't testing then.

 

[dozerdan]

I don't have the book and it was many years ago. They used a variable compression engine and I believe 11:1 was the highest they tested.
They had a very long in-depth chapter about fuels and I assure you there is nothing we have today that they weren't testing then.

I am sure they had no oxygenated fuel or ethanol in the fuel they tested. I know that fuel today isn't like it was in the 60s and 70s. If you got a flame close to the old type gasoline from that era you had a major fire. Not like today's fuel.

Later
Dan

 

[old-cat]

Me thinks you really ought to do some in-depth research, if you really want to know engines.

 

[dozerdan]

Me thinks you really ought to do some in-depth research, if you really want to know engines.

I just cant see any relevance on a test that was done on 4 stoke engines with 1928 gasoline compared to what we are forced to use today.

Later
Dan

 

[old-cat]

I just can't see. I just don't want to see. I refuse to research and learn.

 

[Duane(Pa)]

I've found that 100LL doesn't seem to perform as well. :msp_unsure:

I run 100LL. I also work at an airport, so it's easy for me to get. I don't need the octane or lead for pre ignition or detonation or to protect valve seats etc. I simply, maybe wrongly, think it is made from better petroleum. It smells like gasoline smelled when I was a kid. That was a while ago! :msp_wink: It also has a looooong shelf life and no alcohol, which I know holds less energy by volume than gas. My ex- motorhome would get 10 mpg until they added the corn syrup, then it dropped to 8. I drove it enough to know. Alcohol enhanced (???) fuel also has a lower boiling point. Summer cutting with old metal case saws, and ballooning gas cans have given me further disdain for the ethanol.

Now, I have two confessions: I have never had a fuel problem from stored E gas, but I have taken precautions against it. Self preservation I guess. Maybe more importantly, I don't know what squish is, and I hope someone will explain it. I have to think it is something like deck height, or combustion chamber volume is in automotive performance engines, but I'm guessing. DW

 

[old-cat]

Squish is the area where the flat part of the piston and head come closely together. When the piston comes close to the head it squishes the air/fuel away from the cyl. walls into the combustion chamber. It's somewhat like holding a spray can of flamable liquid and spraying it toward a lighter. VERY rapid burn!

 

[dozerdan]

I just can't see. I just don't want to see. I refuse to research and learn.

Send me a link to this 1928 book and I will read it. It would be interesting to see the antiquated test equipment that was used.

Later
Dan

 

[exSW]

I just can't see. I just don't want to see. I refuse to research and learn.

The fuel we burn to day is different than the fuel from the early 20th century at the molecular level.
Early fuels were the result of straight distillation.The lighter aromatics,benzine,propane and the like came off first followed by gas,kerosine,diesel,bunker oil all the way down to road tar.Also they were distilled from Native North American crudes that come out of the ground purer and more condusive to distillation.Modern fuels especially gasoline are a result of catalytic "cracking"to break the crude down into particular fuels most often gasoline in order to get more gas from a given volumn of crude.And that crude comes from lower quality mideastern well,tar sands and the latest twist "wet" gas from the frack fields here in Pa,NY and Ohio.

 

[MCW]

Putting higher octane fuel in a low spec engine won't make power. However using higher octane fuel, increasing compression, AND advancing the timing certainly will increase power output over lower octance fuel although how much will probably show on the dyno when tested. It is certainly noticable in cars and dyno testing has confirmed this in the past.
You could gain power in older vehicles before knock sensors and auto timing advance by simply using higher octane fuel and manually advancing the timing a few degrees. Newer vehicles do this all for you.
I know that chainsaw motors aren't the same as 4 stroke, valved car motors but the principals on detonation, fuel octane, and timing advance remain the same.

 

[old-cat]

Send me a link to this 1928 book and I will read it. It would be interesting to see the antiquated test equipment that was used.

Later
Dan

I seriously don't think the book is available online. My one time FIL had it and would not let go of it. I searched the Engineering Library at UW to no avail. Mainly, the research I was referring to is the SAE papers.

 

[old-cat]

Study the SAE papers. Univ. of Washington Engineering Library is one place to find them.

Since 1998, I have spent over three thousand hours studying God's Word. Believe me, that is FAR more rewarding than the hundreds of hours I spent studying engine R&D.

 

[wyk]

Since 1998, I have spent over three thousand hours studying God's Word. Believe me, that is FAR more rewarding than the hundreds of hours I spent studying engine R&D.

Didn't know God had so much to say about octane ratings.

 

[MCW]

Didn't know God had so much to say about octane ratings.

Word on the street is that he invented Av Gas.

 

[wyk]

Word on the street is that he invented Av Gas.

Is that what powered the Ark?

 

[MCW]

Is that what powered the Ark?

Allegedly. He wasn't running knock sensors though.

 

[blsnelling]

A 200-225 compression saw will probably gain especially with a timing advance. I'm going to test the 100 octane in my stock 460 and in my brothers 460 that I ported a bb that blows a tad over 200 psi. I plan to also advance the timing 2 deg at a time.

Only if your getting pre-detonation on the lower octane fuel, or if your Maximum Squish Velocity is too high.

As you bump up the ignition timing, you might start pre-detonation. If you do, the higher octane fuel should stop that. If you see a gain in power, the gain is from the timing advance, not the higher octane fuel. The higher octane fuel simply allowed the additional timing advance.

 

[exSW]

Octane always been a funny thing for me.I've had two vehicles that required high octane fuel in my life both wildly different.The first was a '76 Ford F100 with a 300 six,three speed and a 3.00 rear end...what a gutless pig.It actually got about 2 mpg getter gas milage with 93 octane than it did without,didn't run any better.The second couldn't be more different.A '72 Dodge W200.Crewcab,4wd,four speed,4.10's,35's with a '72 440-III(motor home engine,six pack short block with truck heads).It didn't matter what you did spark or timing wise it HAD to have 93 or you got preignition.You could get away with cheap gas in the winter IF it were cold but that was it.Big block mopars run hot if you aren't careful and that had something to do with it but I don't know what was up with that Ford.I wrecked the Ford and used the bits to build another F100(A '75)that had a 302,C-4 and 3.25 rear.What a little screamer and it ran just fine on cheap gas.

Edit:I just talked to my gas supplier.Owns a string of Sunoco/convience stores and is also a car collector(showed me his new killer '72 Chevy 10 Super Cheyenne).Told me his stations have two tanks,87 and 93 octane and the mid grades are mixed by the pump from those two tanks.He also had just talked to his supplier and he said the 93 STILL has ethanol(about 10%).The supplier will sell "pure" gas by the 55 gal drum.I wonder if I pulled up with my 80 gallon farm fuel transport tank if they would fill it?Between my beater five ton dump,the cub cadet,generator and two stroke mix cans I could use up 80 gallon pretty quick.All these sit and need stable fuel till they get used.