Chainsaw fuel

[Hellwig492]

I always run 91 oct. ethanol free fuel in my Stihls, and was thinking of trying 110 oct. race fuel. Anyone tried this and what results did you notice or not notice? Thanks!!

 

[Mad Professor]

No need if you can get non-ethanol, non oxygenated (MBTE) fuel.

Might not store as well as AV gas, but if you run the stuff 1-3 months should be fine.

They went to MBTE here many years ago then to 10% corn fed.

I won't run that in my saws, as many sit for a while, and rubber parts deteriorate with corn/MBTE. Ethanol also reacts with magnesium case parts.

 

[Moss Man]

I was at the corner store buying premium fuel without any ethanol the other day.........and then I woke up from the dream. A group of us were thinking about getting some plane fuel in a drum and all tapping off it, that hasn't happened yet either. There is NO ethanol fee fuel here.

 

[Roanoker494]

I have seen it posted in many threads, by people much smarter than myself, that AV fuel is not going to cause a increase in power unless your saw has over 200psi of compression. It would be like running 100+ octane gas in a Chevette, it may even do more damage than good.

 

[Moss Man]

Yeah, I wouldn't be running it for a power increase, just to get away from the darn ethanol. Mix it right and I'm sure it'd be just fine.

 

[Mad Professor]

I have seen it posted in many threads, by people much smarter than myself, that AV fuel is not going to cause a increase in power unless your saw has over 200psi of compression. It would be like running 100+ octane gas in a Chevette, it may even do more damage than good.

Your Chevette would not have fuel induced rotted fuel system parts.

I ran 100LL , and still do , in a 1968 camaro, it has 195 psi compression. 100LL was highly recommend by Chevrolet for HP engines. The Camaro runs 40 degrees of spark advance, and gets 22 mpg if I don't hit the 4150 4BBL.

And if it was a saw, and the fuel sat 6-12 months, you would not need a new P/C, because the oxygenated fuel decomposed and/or separated the mix.

You are right, no in crease in power for a saw, unless you increase compression.

But if you mix it and store it properly, you can get MANY months without worry of frying a P/C, or rotting out the rubber parts (seals, boots, lines, carb insides.....) of your saws.

It is about $1 more than pump corn fed 93 octane here.

Might be worth it.

 

[sunfish]

Just stay with your 91 oct, eth free gas. Higher oct in a stock saw is not needed. Wish I could get non-eth gas here.

 

[Hellwig492]

I should have mentioned I wasn't looking for HP gains, just better fuel for the saw's fuel system and the issue of storing fuel for a little more than a month at a time. My MS460 pumps 180# of comp. so HP gains might be minimal but probably not noticable. Just looking for the best options for my equipment,I've got a soft spot for my saws! Thanks all for the advice!

 

[Old Crosscut]

Just stay with your 91 oct, eth free gas. Higher oct in a stock saw is not needed. Wish I could get non-eth gas here.

One of these places has got to be close to you!
Ethanol-free gas stations in the U.S. and Canada
I'm lucky--got two right in my town!

 

[sunfish]

One of these places has got to be close to you!
Ethanol-free gas stations in the U.S. and Canada
I'm lucky--got two right in my town!

Thanks for that, looks like the closest is one hour away. Will take a 5 gallon can next time I head that way. I have to drive 23 miles to get premium, so not much farther.

 

[MCW]

We're lucky in Australia because although Ethanol fuel is available we have a wide choice of non Ethanol fuel. I run 98RON Premium Unleaded (BP Ultimate) in all my saws for a number of reasons.

1) It is simply a better fuel with a better formulation.
2) It isn't significantly dearer than standard unleaded.
3) (and the main reason) is that any extra octane gives you a slightly larger buffer in a lean out situation prior to damage occurring - many people forget this.

In a car engine you can advance your timing significantly and have noticable power gains with higher octane fuel prior to detonation occurring. On vehicles with knock sensors and auto advance timing you can gain power WHILE gaining fuel economy at the same time. In fact on many modern vehicles with modern engine management it works out more cost effective to run the higher octane fuel. We worked this out at my previous employer where we had a Toyota Camry fleet that had done millions of kilometres. 98RON Premium was more cost effective per km to run over standard 93RON Unleaded.

However chainsaws don't have auto timing advance and knock sensors

 

[sb47]

Vp makes a ethanol free race fuel that i run in my race bikes. It does contain lead though but it's a direct pour in 105 octane fuel and it runs great in my saws. It will give you 10% more power over any pump gas. You will have to mix 2 stroke oil with it, but if you don't mind the lead it runs great. It if use 91 pump and the use VP U.4.4 my saws rev better and don't bog down when you put pressure on the bar like pump gas will. I have used it for years because I keep plenty on hand for my race bikes.
VP make all kinds of fuels for all kinds of applications.
I had a race motor build that was ported, with the compression bumped up from 10:1 to 14:1 with a bigger carb and better intake mods plus head pipe and muffler mods, bigger valves, bigger cam. The works basically. My stock motor went from 23 HP stock to 59 HP after all the mods. I raced that motor with nothing but keeping good oil in it and I practiced 4 days a week and raced it for 6 years and I never did anything but change the oil.
I ran a Honda 400ex in a class of all 450's and I won the championship 5 years running on the same motor.
What killed the bike wasn't the motor, I let a friend race my bike for points because his bike was down. He landed on the shiftier lever on a big jump and bent the shiftier forks, stripping out 3rd gear. I had the lower end rebuilt but left the top end the same other then ringing it. All the mods and all the racing never hurt that motor one little bit. In fact I still ride it. Just as it was when I stopped racing. I ran VP U.4.4 the whole time with zero issues.

110 octane is a little high for a stock 10:1 piston. It's just gonna make you saw run hot and you will have to re jet if you run 11o octane. Unless you bump the compression to at least 12:1 but you will still need to re jet.

 

[BigMoneyGrip]

I have a 290 thats 11 years old. It's had avgas since day one and still has the original fuel lines and all. It sits a lot and doesn't get used on a normal basis. I use it because of the storage life and a side benefit is no ethanol. I know of several saws much newer than mine and they've had fuel lines replaced.

 

[full chizel]

I’ll pass on breathing lead fumes. I use Efree 89 but if i need to replace a fuel line or carb kit it’ll be easier than a lung.

 

[av8or3]

+ this

I have seen it posted in many threads, by people much smarter than myself, that AV fuel is not going to cause a increase in power unless your saw has over 200psi of compression. It would be like running 100+ octane gas in a Chevette, it may even do more damage than good.

 

[av8or3]

Something else maybe worth considering. 100LL (low lead) avgas has 7 times the amount of TEL (tetra ethel lead) that 93 octane cargas of yesteryear had. Fuels are dyed to reflect their lead content. 100LL is blue ,100 is green ,135 is purple. When TEL was in automotive fuel 93 octane was pink (I think) and 89 was amber. Amoco 93 octane was clear because it wasn’t required to be dyed, no lead content.
Anyway, it’s been said somewhere that the ethanol reacts with magnesium, it actually the water in the ethanol but as bad as that is, you should see how aluminum and magnesium return to their natural state when covered in the exhaust trail underwing on piston engine aircraft. Lead is very corrosive, and poisonous.
Avgas is formulated to allow a piston engine to operate at altitude. It has a different vapor pressure than cargas to prevent vapor lock. The high lead is used for cooling and to booste the octane rating. It is indeed ethanol free. And the aircraft engine was designed to run on it.
If you can’t tell I’m opinionated on the subject.

 

[sb47]

Been a long time since I have bought any avgas but the last time it was brown in color. VP U4 was clear and it was a leaded fuel. Then they replaced it with VP U4.2 was green and still leaded, then they changed to U4.4 witch is blue, and it's still leaded.

Here is a list of all of VP's fuel line and whats in it.
https://vpracingfuels.com/master-fuel-table/
If you notice color does not indicate weather it's leaded or not. Some leaded fuel are colored and some are not. It still list U4.4 as green, but it's not, it's dark blue. I just bought some yesterday and it's blue, even though they list it as green.
Also notice the octane rating numbers. They use 2 different numbers, the RON and MON. Notice the difference in the numbers. The RON is the (research octane number) and the MON is the (motor octane number).

Sunoco fuel uses different colors for there fuels and again color does not dictate if it's leaded or not.
https://www.sunocoracefuels.com/fuel-selector
More sunoco info
https://www.sunocoracefuels.com/tech-corner

BE WARNED: Most race and high performance fuels are very corrosive so do your research.

 

[sb47]

I did some research in my area and some Buc-ee's do carry ethanol free fuels. There is one about 40 miles from me that carries it. I called to double check and not all pumps are ethanol free so make sure you read the pump or call to make sure before you drive over.

Buc-ee's locations, sorry but there only down south in Texas.
https://www.buc-ees.com/locations.php

 

[SamT1]

Something else maybe worth considering. 100LL (low lead) avgas has 7 times the amount of TEL (tetra ethel lead) that 93 octane cargas of yesteryear had. Fuels are dyed to reflect their lead content. 100LL is blue ,100 is green ,135 is purple. When TEL was in automotive fuel 93 octane was pink (I think) and 89 was amber. Amoco 93 octane was clear because it wasn’t required to be dyed, no lead content.
Anyway, it’s been said somewhere that the ethanol reacts with magnesium, it actually the water in the ethanol but as bad as that is, you should see how aluminum and magnesium return to their natural state when covered in the exhaust trail underwing on piston engine aircraft. Lead is very corrosive, and poisonous.
Avgas is formulated to allow a piston engine to operate at altitude. It has a different vapor pressure than cargas to prevent vapor lock. The high lead is used for cooling and to booste the octane rating. It is indeed ethanol free. And the aircraft engine was designed to run on it.
If you can’t tell I’m opinionated on the subject.

There’s a lot of myth and lore around AV gas. Most of it stems from the folks who sell race fuel not wanting the competition. I’ve run race engines for years on it including Volkswagen with mag/aluminum alloy heads and cases. I could never tell any 1/4 mile time differences nor have I ever needed to turn back the boost or timing on my turbo vw rail. At some point the octane isn’t enough, but it’s dang good for most applications. Be aware though that you will make less power using it in an engine designed for 87 as well as eventually ruin the O2 sensors and plug the catylitic converter if applicable.
I run it in all my small engines that sit around, it makes a huge difference in how easy they crank up after a year. My boat will bust right off like it ran yesterday when it warms up. I just fuel it with avgas before the last time I use it. Then top off with “ ethanol free” 93 when I’m ready to play .

If your buying “ethanol free” pump gas be aware the hose and pump will have a lot of the last selection in it. if your just making a gallon of mix for a chainsaw you may get all E85 or someone’s 87 E10. I carry a can separate that’s for the atv and pump off a gallon or so in it first.

 

[sb47]

There’s a lot of myth and lore around AV gas. Most of it stems from the folks who sell race fuel not wanting the competition. I’ve run race engines for years on it including Volkswagen with mag/aluminum alloy heads and cases. I could never tell any 1/4 mile time differences nor have I ever needed to turn back the boost or timing on my turbo vw rail. At some point the octane isn’t enough, but it’s dang good for most applications. Be aware though that you will make less power using it in an engine designed for 87 as well as eventually ruin the O2 sensors and plug the catylitic converter if applicable.
I run it in all my small engines that sit around, it makes a huge difference in how easy they crank up after a year. My boat will bust right off like it ran yesterday when it warms up. I just fuel it with avgas before the last time I use it. Then top off with “ ethanol free” 93 when I’m ready to play .

If your buying “ethanol free” pump gas be aware the hose and pump will have a lot of the last selection in it. if your just making a gallon of mix for a chainsaw you may get all E85 or someone’s 87 E10. I carry a can separate that’s for the atv and pump off a gallon or so in it first.

I can definitely tell the power difference in pump gas and VP race fuel. When cutting with my chain saw and using pump gas I can bog down and stop the chain if I bear down too hard on the saw. But if I run the U4.4 I can bear down twice as hard and it wont bog down and stop the chain from turning. It make a big difference in my race bikes as well. I can definitely tell the power difference between the fuels. I tried avgas a few times and I didn't notice any power difference at all.
Octane ratings are basically the difference in how much heat it takes to ignite the fuel. The higher the compression the higher the octane needs to be.
It also depends on how much heat it creates during ignition. High octane does nothing in a motor with low compression ratings, except creating more heat, not more power.

Dont skip on fuel if your looking for more power. Try some actual race fuel and see what differences you see.