Redwood City, California Ethanol Free gas

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I usually run Shell 91 no ethanol v-power, but if worse came to worse I'd run 100ll from my local airport. Right now it's $4.75 a gallon. The folks that run it know me, so I just walk in with my can and fill it up. Little bit of lead in there isn't gonna hurt a chainsaw, older generator, older tractor etc.
 
I usually run Shell 91 no ethanol v-power, but if worse came to worse I'd run 100ll from my local airport. Right now it's $4.75 a gallon. The folks that run it know me, so I just walk in with my can and fill it up. Little bit of lead in there isn't gonna hurt a chainsaw, older generator, older tractor etc.
It won't hurt thw equipment at all. It will effect the operator.
 
Stihl designs its motors to accommodate 10% ethanol... and prior posts that *any* amount of ethanol is fine with proper tuning is accurate.

The problem I'm struggling with is on an mtronric system there is no H L adjustment on the carb... its done by the mtronic solenoid and essentially the parameters set by the stihl computer... computed second by second based on whatever sensors they're using to drive the mtronic.

IDK if the mtronic is measuring air temp or motor temp or if there is a wide or narrow band lambda stuck in there 🤣 --i've not bothered to pull an mtronic saw apart.

But for *any* "electronic choke" or FI system it can only adjust within the parameters its given... unlike for instance a carb with a main jet and an idle jet and mix screws and limiters... which can be adjusted to run pretty much *anything* from pure nitro to pure ethanol... to use extreme examples.

So I've got a choice... pull my mtronic system apart and see if I can find a way to tweak the parameters to accommodate the mystery E? mix I'm getting out of CA gasoline... which is probably changing every time I'm at the pump...

and even then I'm no computer nerd so no guarantee I'd be able to tweak it right... (no offense to computer nerds... I love those guys with their o2 sniffers and a/f ratios and dynos and laptops--I can't wait until some of them invent a chip or whatever to tune our mtronic saws--and some day they will)

In the meantime I pay ~30% more for fuel for my saw... and it runs beautifully and predictably...

Until somebody invents a way to tune the mtronic (or if they have already, I learn how) the best thing I could do is find someone with an airplane and make friends with them so I can get avgas 🤣

(good luck with that in CA after 9/11)

I'm sure a whole bunch of folks have torn mtronric systems down and have figured out the sensors etc but I haven't met any of them...
 
At one point premium 91 pump was $7 a gallon here in CA. Filling up cars that were close to empty the pump automatically maxes out when it hits $100... and the tank still wouldn't be full... when you'd swipe the credit again to finish filling the tank you'd get a fraud alert (?!) 🤣

So I used to have to use my credit card for the first fill and my ATM card for the top-off (😳‼️)

So... yeah i'd throw a party if I could buy ethanol free for $4 a gallon 😁

But i'm probably going to have to leave California... everything has changed... (I know it changes everywhere)

But I'm a relic and can't relate anymore... people asking me what my pronouns are 🤣

The first time it happened someone had to explain it to me... (shrug)

I'm sure looking forward to somebody inventing a tuner for the mtronic/FI Stihl stuff... because if I live long enough... they most certainly will
 
Stihl designs its motors to accommodate 10% ethanol... and prior posts that *any* amount of ethanol is fine with proper tuning is accurate.

The problem I'm struggling with is on an mtronric system there is no H L adjustment on the carb... its done by the mtronic solenoid and essentially the parameters set by the stihl computer... computed second by second based on whatever sensors they're using to drive the mtronic.

IDK if the mtronic is measuring air temp or motor temp or if there is a wide or narrow band lambda stuck in there 🤣 --i've not bothered to pull an mtronic saw apart.

But for *any* "electronic choke" or FI system it can only adjust within the parameters its given... unlike for instance a carb with a main jet and an idle jet and mix screws and limiters... which can be adjusted to run pretty much *anything* from pure nitro to pure ethanol... to use extreme examples.

So I've got a choice... pull my mtronic system apart and see if I can find a way to tweak the parameters to accommodate the mystery E? mix I'm getting out of CA gasoline... which is probably changing every time I'm at the pump...

and even then I'm no computer nerd so no guarantee I'd be able to tweak it right... (no offense to computer nerds... I love those guys with their o2 sniffers and a/f ratios and dynos and laptops--I can't wait until some of them invent a chip or whatever to tune our mtronic saws--and some day they will)

In the meantime I pay ~30% more for fuel for my saw... and it runs beautifully and predictably...

Until somebody invents a way to tune the mtronic (or if they have already, I learn how) the best thing I could do is find someone with an airplane and make friends with them so I can get avgas 🤣

(good luck with that in CA after 9/11)

I'm sure a whole bunch of folks have torn mtronric systems down and have figured out the sensors etc but I haven't met any of them...
As I understand it, there's a temp sensor, and rpm sensor. Then the fuel and ignition maps. The m-tronic does t have an issue compensation for extra fuel, as seen by the thousands of ported saws out there. I know every now and then it sends a lean pulse and compares expected rpm changes to the maps then adjusts fuel accordingly. I'm not certain how the temp sensor factors in, other then start up conditions. I'm fairly sure it's located (temp sensor) in the ignition moduel and outta up to the case.
Having said all that, while it is capable of flowing more then enough fuel for ethonal increases, I doubt it had the appropriate fuel/ignition maps to compensate. My comments were strictly manual carb in the case of excess ethanol content.
Which brings me to another thought, several years ago there were a lot of gas stations that tested well above 10% ethanol locally. If someone wouldn't have tested the fuel, I doubt anyone would have noticed. Meh, too few people worry about the gas out of the pump.
 
As I understand it, there's a temp sensor, and rpm sensor. Then the fuel and ignition maps. The m-tronic does t have an issue compensation for extra fuel, as seen by the thousands of ported saws out there. I know every now and then it sends a lean pulse and compares expected rpm changes to the maps then adjusts fuel accordingly. I'm not certain how the temp sensor factors in, other then start up conditions. I'm fairly sure it's located (temp sensor) in the ignition moduel and outta up to the case.
Having said all that, while it is capable of flowing more then enough fuel for ethonal increases, I doubt it had the appropriate fuel/ignition maps to compensate. My comments were strictly manual carb in the case of excess ethanol content.
Which brings me to another thought, several years ago there were a lot of gas stations that tested well above 10% ethanol locally. If someone wouldn't have tested the fuel, I doubt anyone would have noticed. Meh, too few people worry about the gas out of the pump.

30 years ago the KTM 690/450 motorcycles to race the pari-dakar (even the OEM from the factory models) had a map switch under the seat... and one of the 3 settings was for "bad gas"

But these days the FI computers are unbelievably advanced... the FI on a modern car is *miraculous* and can automatically adapt for the worst garbage fuel obtainable in the middle of places like parts of africa or whatnot.

Fact is, most people pumping high octane gas don't need it... their car can gobble 85 octane just fine...

I think that's why we aren't hearing about pumps mismatching the advertised ethanol or octane anymore... modern cars are so good we can't feel it

That said, racers still play with fuel maps... and stihl's mtronic is limited to the parameters it has... it can't adjust for "100% gasoline" fuel right? I think the pumps where I live have >20% ethanol in them... if I'm feeling bored enough some day maybe I'll test some 🤣
 
At one point premium 91 pump was $7 a gallon here in CA. Filling up cars that were close to empty the pump automatically maxes out when it hits $100... and the tank still wouldn't be full... when you'd swipe the credit again to finish filling the tank you'd get a fraud alert (?!) 🤣

So I used to have to use my credit card for the first fill and my ATM card for the top-off (😳‼️)

So... yeah i'd throw a party if I could buy ethanol free for $4 a gallon 😁

But i'm probably going to have to leave California... everything has changed... (I know it changes everywhere)

But I'm a relic and can't relate anymore... people asking me what my pronouns are 🤣

The first time it happened someone had to explain it to me... (shrug)

I'm sure looking forward to somebody inventing a tuner for the mtronic/FI Stihl stuff... because if I live long enough... they most certainly will
Blackbeard - I’m in California as well, and just like you, have to sometimes make my pronouns available, which are: Fahk and You. They seem to work… 🤣
 
Stihl designs its motors to accommodate 10% ethanol... and prior posts that *any* amount of ethanol is fine with proper tuning is accurate.

The problem I'm struggling with is on an mtronric system there is no H L adjustment on the carb... its done by the mtronic solenoid and essentially the parameters set by the stihl computer... computed second by second based on whatever sensors they're using to drive the mtronic.

IDK if the mtronic is measuring air temp or motor temp or if there is a wide or narrow band lambda stuck in there 🤣 --i've not bothered to pull an mtronic saw apart.

But for *any* "electronic choke" or FI system it can only adjust within the parameters its given... unlike for instance a carb with a main jet and an idle jet and mix screws and limiters... which can be adjusted to run pretty much *anything* from pure nitro to pure ethanol... to use extreme examples.

So I've got a choice... pull my mtronic system apart and see if I can find a way to tweak the parameters to accommodate the mystery E? mix I'm getting out of CA gasoline... which is probably changing every time I'm at the pump...

and even then I'm no computer nerd so no guarantee I'd be able to tweak it right... (no offense to computer nerds... I love those guys with their o2 sniffers and a/f ratios and dynos and laptops--I can't wait until some of them invent a chip or whatever to tune our mtronic saws--and some day they will)

In the meantime I pay ~30% more for fuel for my saw... and it runs beautifully and predictably...

Until somebody invents a way to tune the mtronic (or if they have already, I learn how) the best thing I could do is find someone with an airplane and make friends with them so I can get avgas 🤣

(good luck with that in CA after 9/11)

I'm sure a whole bunch of folks have torn mtronric systems down and have figured out the sensors etc but I haven't met any of them...
Ethanol destroys 2 stroke engines, period.
 

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