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robertcope

January 2020 Member Days

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13 minutes ago, joesurf79 said:

This is my question as well. From what I've read / heard (credible sources or not, who knows) the equivalent octane rating of e85 is approx 105. It's 30% lower in BTU content so you have to run a ton more of it (needing bigger pumps, injectors, resistant fuel lines, etc). And its hygroscopic like brake fluid, so it pulls water from the atmosphere, and is highly corrosive to susceptible metals. But for a toy car under boost that you can nearly run dry and park with some ethanol stabilizer or some 96 octane in the tank as insurance - why not?

I run e85 in the BRZ NA and the flex fuel tune i have allows any mix from 100% 93 to 100% e85. You can tell there's more power on e85. I guess its allowing more radical ignition timing?

Also, the e85 usually undergoes more complete combustion and has a cooling effect on the combustion chamber (partially due to the water content). The biggest downside is the lower energy density (that 30% you mentioned) and the hassle of sourcing and usually bringing your own e85 (different sources also will give different concentrations so your local station might suck). Also, since it absorbs water you have to be careful (or just shouldn't) storing it for long periods of time.

If we had more e85 stations like up north, just about everyone would run it. Metals aren't the main issue with ethanol, it's seals that aren't meant for it. Older rubber seals will be dried out by the ethanol (it's a solvent for the volatiles that keep the rubber pliable). The army did a study in the late 70's/early 80's and basically as long as you aren't running methanol (great for power, bad for engine longevity) your engine will be happy (no increased wear) with gasoline, gasoline/ethanol mix (10% like we've got now), and all the way up to the e85 (it's hard to get more than 85% ethanol since that's close to the limit you can get with distillation). The main problem with methanol was that it produced formic acid as a byproduct of combustion which increases wear (same reason why drinking moonshine is dangerous, if you distill alcohol with insufficient oxygen you get methanol instead of ethanol and the methanol gets metabolized into toxic compounds like formaldehyde). 

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10 minutes ago, BRZ4Science said:

Also, the e85 usually undergoes more complete combustion and has a cooling effect on the combustion chamber (partially due to the water content). The biggest downside is the lower energy density (that 30% you mentioned) and the hassle of sourcing and usually bringing your own e85 (different sources also will give different concentrations so your local station might suck). Also, since it absorbs water you have to be careful (or just shouldn't) storing it for long periods of time.

If we had more e85 stations like up north, just about everyone would run it. Metals aren't the main issue with ethanol, it's seals that aren't meant for it. Older rubber seals will be dried out by the ethanol (it's a solvent for the volatiles that keep the rubber pliable). The army did a study in the late 70's/early 80's and basically as long as you aren't running methanol (great for power, bad for engine longevity) your engine will be happy (no increased wear) with gasoline, gasoline/ethanol mix (10% like we've got now), and all the way up to the e85 (it's hard to get more than 85% ethanol since that's close to the limit you can get with distillation). The main problem with methanol was that it produced formic acid as a byproduct of combustion which increases wear (same reason why drinking moonshine is dangerous, if you distill alcohol with insufficient oxygen you get methanol instead of ethanol and the methanol gets metabolized into toxic compounds like formaldehyde). 

Also - there are claims that ethanol "washes cylinders" more than gasoline does? Accelerating viscosity break-down of the engine oil, etc. I change engine oil excessively, and worry less about follow on wear effects, but all the UOAs have come back looking great so *shrugs shoulders*

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My car has the 20 gallon fuel cell.  It won't hurt me to switch and that is my plan but some will need to consider it.  Also this brings the need to tote E85 to the track as well.  I have a trailer and can do this but others who might drive to the track could hurt them to do so.

Good points but E85 shouldn't hurt that much considering we are already running these motors hard unlike a normal motor.  Drag boys live by the stuff.  New new pumps are good for it and my entire fuel system.  My only thing left to do is upgrade the injectors and get a retune.  My 60lbs won't be enough so I'll need 80lbs (or 1050cc's)

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1 hour ago, Talley said:

My car has the 20 gallon fuel cell.  It won't hurt me to switch and that is my plan but some will need to consider it.  Also this brings the need to tote E85 to the track as well.  I have a trailer and can do this but others who might drive to the track could hurt them to do so.

Good points but E85 shouldn't hurt that much considering we are already running these motors hard unlike a normal motor.  Drag boys live by the stuff.  New new pumps are good for it and my entire fuel system.  My only thing left to do is upgrade the injectors and get a retune.  My 60lbs won't be enough so I'll need 80lbs (or 1050cc's)

Your car is VERY thirsty.  think of how much fuel you go through now.   Double it when you develop more speed and are on the throttle more time/lap.   and now add another 30-50% for the greater consumption due to the E85.   Fast guys I know in decent power cars go through 15-20gallons PER SESSION on track.

One guy I talked to recently with a ~600hp Camaro said he converted to E85 and would go through  >100 gal in a weekend.  He converted back to gas due to the hassles.

49 CFR covers transportation of fuels, and the internet opinion is that 110gal of any type of fuel is the max you can carry in a single load, which includes furl drums and anything in the car.

Also, many tracks have a 5gal container size limit.   you can bring as many 5 gal containers as you want, but you cannot bring a 55gal drum to the track.

 

Soooo....  Be armed with all of the information before you convert the car to E85 and make sure it's the correct decision vs. "I can make more power on it"..

... And without beating on that horse any more, more power is the last thing you need right now, young man. 😉 

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2 hours ago, Matt93SE said:

Your car is VERY thirsty.  think of how much fuel you go through now.   Double it when you develop more speed and are on the throttle more time/lap.   and now add another 30-50% for the greater consumption due to the E85.   Fast guys I know in decent power cars go through 15-20gallons PER SESSION on track.

One guy I talked to recently with a ~600hp Camaro said he converted to E85 and would go through  >100 gal in a weekend.  He converted back to gas due to the hassles.

49 CFR covers transportation of fuels, and the internet opinion is that 110gal of any type of fuel is the max you can carry in a single load, which includes furl drums and anything in the car.

Also, many tracks have a 5gal container size limit.   you can bring as many 5 gal containers as you want, but you cannot bring a 55gal drum to the track.

 

Soooo....  Be armed with all of the information before you convert the car to E85 and make sure it's the correct decision vs. "I can make more power on it"..

... And without beating on that horse any more, more power is the last thing you need right now, young man. 😉 

Thanks for the insight. I was aware of the 49 CFR but not aware of the track limitations.  It wasn't for the power more for the octane.  Right now I'll stick to the 100 octane mix since it's what my uncle used.  If I remember right though the 49CFR allowed 110 gallons not including the vehicle.  (aux storage).

But yes I completely agree with the consumption.  My "novice" level I was using only 4 gallons per 20min session.   My uncle being an instructor is the only data I have on fuel consumption and at the Road america was his biggest fuel hungry track would use 10 gallons in a 20 min session which he said was right around 3.4mpg.   He said michigan, putman, mid ohio etc would average around 4.5-5mpg.    Right now I'm getting a bit over 6mpg  😛  Don't get me wrong... I'm not changing anything until I need to.  Which is literally years away. 

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On 1/23/2020 at 4:57 PM, Talley said:

Thanks for the insight. I was aware of the 49 CFR but not aware of the track limitations.  It wasn't for the power more for the octane.  Right now I'll stick to the 100 octane mix since it's what my uncle used.  If I remember right though the 49CFR allowed 110 gallons not including the vehicle.  (aux storage).

But yes I completely agree with the consumption.  My "novice" level I was using only 4 gallons per 20min session.   My uncle being an instructor is the only data I have on fuel consumption and at the Road america was his biggest fuel hungry track would use 10 gallons in a 20 min session which he said was right around 3.4mpg.   He said michigan, putman, mid ohio etc would average around 4.5-5mpg.    Right now I'm getting a bit over 6mpg  😛  Don't get me wrong... I'm not changing anything until I need to.  Which is literally years away. 

Aux storage = anything OTHER than the tow vehicle's tank.   so you can have a aux tank in the bed of the tow truck, a drum of fuel in the trailer, and whatever is in the car being towed--  all of those must total 110gal or less.  

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15 hours ago, Paladin said:

Guys when is the next members day??

next weekend looks open on their calendar..

 

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5 hours ago, Matt93SE said:

Aux storage = anything OTHER than the tow vehicle's tank.   so you can have a aux tank in the bed of the tow truck, a drum of fuel in the trailer, and whatever is in the car being towed--  all of those must total 110gal or less.  

oh snap... ok.  Thanks for the clarification.  And my uncle told me he was using up an average of 85 gallons of fuel a weekend when he was tracking my car.  This was the 93/100 mix mentioned earlier.

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6 hours ago, Hollywood said:

@Paladin I won’t be able to make this weekend 😕 

Apparently neither will I since you cannot make it! Family requested a long weekend over Austin and San Antonio andI told them "it depends" ....now I can say "we go" 😄 

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