Let's talk gas/oil mix...

[Shannon Muth]

I have seemingly used just about every gas/oil combination in the last 15 years with various ratios. The 8-10 ounce per gallon is what I use now. I began using Red Line 2 stroke race oil because I also fly RC large scale and DA engines strongly recommends it. When I used to make my own Nitro fuel I used Red Line's alcohol version as well.

 

[ALLAN YUEN]

Walbro K3-WYTA Spiral Diaphragm I have this installed in my 990 carb. Don't have to worry about ethanol destroying the diaphragm.

Very interested then new learning to install products

 

[David Bryant]

Iam going to be running the premix VP racing gas for 2 stroke motors that they make you can’t go wrong with their products

same here.

 

[Paul Cooper]

Very interested then new learning to install products

Installing the Spiral Diaphram isn't to bad . I watched the video in the link as I was installing them in my 990 and 1107 carbs for the baja.

 

[John Beardslee]

Just my 2 cents. I don’t run gas boats but do have many giant scale gas airplanes and raced full sized outboards. My go to choices for gas are always 100 octane av gas or Coleman because of manufacturing consistency. The regulations and liability for processing these two give great confidence that they are always the same where ever I purchase them. The oils don’t seem to be much of a concern as long as you run enough. My preference is Redline because it is easy to clean off. Second is the Klots w/castor blend. I’ve used since the 1960’s

 

[Wasted wages]

It really surprises me that so many people are running camp fuel...I always thought of it as a low grade fuel suitable for lanterns and stoves.

Didn't even know that it would burn in an engine... thought it was more like kerosene.
Does camp fuel even have an octane rating ?

 

[John Beardslee]

It really surprises me that so many people are running camp fuel...I always thought of it as a low grade fuel suitable for lanterns and stoves.

Didn't even know that it would burn in an engine... thought it was more like kerosene.
Does camp fuel even have an octane rating ?

It’s white gas, or at least what we called it years ago. It is low octane but most engines are low compression and it works for them. The stove and lantern fuel aspect is why it so consistent, liability laws and regulations dictates it. The engine manufacturer will recommend what octane to run. BME engines specified premium or high octane gas, if you didn’t run it, the engine would detonate and I’ve seen people blow the ears right off the jug/cylinder on 100 cc two cylinder engines. Running higher octane in a low compression engine doesn’t seem to cause any issues from my experience. I’ve been told it may create a little more heat. I run all av 100 octane gas now so I only inventory one gas. I even run it in my generator. I will last 10 years in a jug and not varnish up.

 

[Wasted wages]

may seem like a stupid question, but where do you get av gas ?? do they sell it to anyone at like a local small airport?

 

[Hydro Junkie]

Yup, you get it at the General Aviation type of airport. Be aware, not all fields will sell to people without an aircraft due to the possibility of someone putting it in their car/truck, something that is(or at least was) illegal in some states. I can get a gallon or two at Arlington Airport(AWO) at a time but any more than that, I'd better be picking it up in a plane's fuel tank With that said, I can't buy avgas at all at Paine Field(PAE), home of the Boeing wide bodied aircraft. They didn't tell me why, just said they wouldn't sell it unless it went right into an airplane's tank(s)

 

[John Beardslee]

I’ve always told them exactly what I was using it for and I usually buy 5 gallons at a time. Take your phone with pictures and show them some of your toys and get to know them and you should be good.

 

[Hydro Junkie]

I did tell them what I wanted it for. Paine Field said no, Arlington gave me a limit. I'm sure each airport has its own rules, I just listed the ones I have first hand knowledge of.

 

[Wasted wages]

Hydro,,,

Arlington ( AWO ),, is that the one right off of 360 and I-20 ??

 

[John Beardslee]

For the most part my purchases have been at the smaller local general aviation locations. The largest would be at Sarasota-Bradenton in FL. If you have a RC flying club in your area it might be worth contacting them, many of their members have contacts with full size aviation and my be able to help.
John

 

[Grimracer]

To those reading in,

To me the largest part of this is the octane level. I for one have little need for anything over 70 (camp fuel).. the added benefit is no alcohol. Those two simple things make it (to me) an easy choice.

BUT.. opinions very.. and that's cool too. I suspect we might also have varying opinions on what performance means as well.

Be well all.

Grim

 

[Buckshot]

Hydro,,,

Arlington ( AWO ),, is that the one right off of 360 and I-20 ??

The one your thinking of is Arlington Municipal Airport (GKY) in Texas. I used to live a few miles from there in Mansfield, TX. John Bordon still lives near there also.
Arlington Municipal Airport (AWO) is in Washington.

 

[Wasted wages]

Ha !! I guess having the correct state does make a big difference!! I used to work in Grand Prairie and that little airport was close by...
Bell helicopter is right there too.

We would go to the little terminal for lunch, they had a great burger joint inside ... watch all the planes and heli's do touch and go's..

 

[Hydro Junkie]

The one your thinking of is Arlington Municipal Airport (GKY) in Texas. I used to live a few miles from there in Mansfield, TX. John Bordon still lives near there also.
Arlington Municipal Airport (AWO) is in Washington.

And, to be more exact, it's about half way between Seattle and the Canadian border, just off I-5. It started out as a Naval Air Station, just like Paine Field in Everett, Sand Point in Seattle and the present NAS Whidbey Island.
Here's a googlemaps link to the field:
Google Maps

 

[LohringMiller]

Let me post our fuel test results. This was a new M&D Zenoah that broke in over the test series. See the first graph. We didn't test nitroethane which some people feel will boost power. However, nitromethane actually reduced power in our tests. You can mix a little with straight gasoline (5%), but with ethanol, a mutual solvent, you can mix in a lot. The ethanol and methanol mixes need a richer needle. Below are some summary graphs. The first shows the result of break in. The second shows that the ethanol containing fuels might have a slight edge AT THE BEST NEEDLE. The next graph shows what happens at the same needle. The fourth graph shows what happens when you add a lot of methanol. It might give a slight edge over straight gasoline, but remember the precision of these tests. The last graph shows what happens when you add nitromethane. We could get 5% in straight gasoline and a lot more in the ethanol containing gasoline/ethanol mixes. It didn't help.

Lohring Miller

 

[LohringMiller]

This final graph shows the result of different oils at the same mix. It also gives an idea of the precision of our dyno. That's as close as you get on back to back runs. Remember that when you look at slight differences in the above tests.

Lohring Miller

 

[John Beardslee]

Let me post our fuel test results. This was a new M&D Zenoah that broke in over the test series. See the first graph. We didn't test nitroethane which some people feel will boost power. However, nitromethane actually reduced power in our tests. You can mix a little with straight gasoline (5%), but with ethanol, a mutual solvent, you can mix in a lot. The ethanol and methanol mixes need a richer needle. Below are some summary graphs. The first shows the result of break in. The second shows that the ethanol containing fuels might have a slight edge AT THE BEST NEEDLE. The next graph shows what happens at the same needle. The fourth graph shows what happens when you add a lot of methanol. It might give a slight edge over straight gasoline, but remember the precision of these tests. The last graph shows what happens when you add nitromethane. We could get 5% in straight gasoline and a lot more in the ethanol containing gasoline/ethanol mixes. It didn't help.

Lohring Miller

View attachment 288854View attachment 288855View attachment 288856View attachment 288857View attachment 288858

Lohring,
Did you increase the compression ratio? We found best performance from higher octane and alky engines required 12:1 or 14:1 compression ratios. Some of the large outboards had compression release valves installed in order to rope start them.