cheap gas

[onemoremile]

Just an FYI, I pulled into a gas station with an empty tank and an idea. Rather than 3.90 for 94 octane premium I put in a half tank of 87 @ 3.70 and filled it the rest of the way with e85 @ about 2.75. I saved about 12 bucks on the fillup and the car had never run better. Since e85 is 105 octane this tank averaged out to 95-96 octane. Gas mileage was pretty much the same as always at 22-24 average for mixed driving.

[Nebone]

Sounds like a plan but I haven't see any ethanol E85 station in New England and Premium is $4.00+

[onemoremile]

Yeah, same here. That was a few tanks ago. There aren't any e85 stations near my house or work. If you do this you should put the regular gas in first. In theory, if the e85 goes in first it could dissolve sediment and clog the fuel filter. If that is really the case then I could just run straight e85 for a couple tanks, change the filter, and end up with a clean tank and filter.

[BLACKa4QUAT]

cars that arent made for e85 could have corrosion problems from ethanol in the fuel system.

[destrolock]

Yeah, same here. That was a few tanks ago. There aren't any e85 stations near my house or work. If you do this you should put the regular gas in first. In theory, if the e85 goes in first it could dissolve sediment and clog the fuel filter. If that is really the case then I could just run straight e85 for a couple tanks, change the filter, and end up with a clean tank and filter.

Quick questions,

Was this in the Avant or the Outback? Did you make any mods to the fuel lines to be able to use e85?

Too bad the closed station to me is 100 miles away in San Diego.. this is a great idea. Plus we only get 91 craptaine here in CA which is annoying to say the least.

[djwimbo]

If ya think about it, E85 and standard fuel are made out of the same stuff, I don't remember having to convert anything to run it.
E85 is just 85% alcohol, normal Premium fuel is just a modified alcohol.

[onemoremile]

Normal gasoline is about 15% ethanol. Do the math and my mix was about 50%.

I've heard all about the fuel line issue and that is one reason I went half and half. I also didn't want to run too lean by running e85 on a premium gas specific tune. There have been reports of Audi drivers in Brazil running ethanol for years without problems. I'm not saying that there can't be problems in the future but their experience helps ease the mind.

This was in the Audi. The OB runs 87 octane all day long and loves it.

[BLACKa4QUAT]

it would be interesting to see about those brazillians running their ethanol in their cars, and what mod's, if any, they need to make, or issues from running it. ethanol is pretty damn cheap for high octane.

[mike-2ptzero]

Normal gasoline is about 15% ethanol. Do the math and my mix was about 50%.

I've heard all about the fuel line issue and that is one reason I went half and half. I also didn't want to run lean by running e85 on a premium gas specific tune. There have been reports of Audi drivers in Brazil running ethanol for years without problems. I'm not saying that there can't be problems in the future but their experience helps ease the mind.

This was in the Audi. The OB runs 87 octane all day long and loves it.

Well the more ethanol you run in the tank the leaner the car is going to be. Did you log the car at all when you did this or check to see what your fuel trim readings are on block 032?


It might have cost you less money to fill the tank up but since you need to burn more of that fuel to stay at the correct AFR you will just end up burning thru that tank of fuel quicker.

[djwimbo]

it would be interesting to see about those brazillians running their ethanol in their cars, and what mod's, if any, they need to make, or issues from running it. ethanol is pretty damn cheap for high octane.

Buddy of mine runnin a Galant VR4 runs E85. He was able to run 30psi w/o any timing retard. It's not slow. 94 oct he ran high 12's on the first turbo, E85 ran mid 12's no tuning.
11's on a quick tune second turbo, and he's working on his tune for E85 for the second one. He's hoping for mid 10's, soon to be proven.

[pac1085]

Do you have a wideband o2 sensor? I don't know how well the factory ECU can correct the mixture but you are running lean.

[pac1085]

Buddy of mine runnin a Galant VR4 runs E85. He was able to run 30psi w/o any timing retard. It's not slow. 94 oct he ran high 12's on the first turbo, E85 ran mid 12's no tuning.
11's on a quick tune second turbo, and he's working on his tune for E85 for the second one. He's hoping for mid 10's, soon to be proven.

your buddy has no clue what he's talking about if he claims he switched from 94 oct to e85 with no tuning.

switching from gasoline to e85 requires about 40% more fuel to maintain the same lambda reading as gasoline...been there done that

[bob12312357]

Umm just an FYI, ethanol is not used in Avgas100LL and for a plane to run on E85 the entire fuel system must be brought up 2 spec due to the good risk of erosion of fuel lines and O-rings.

[Nebone]

If you read the gauge cluster it says Unleaded Fuel Only. European stations and probably Brazilian ones still have Leaded gasoline and cars are meant to run it.

BTW. USA is 111th in the world in respect to most expensive gasoline. It's still cheap here compared to other countries compared to their wages.

I feel like I go through gas real fast is because I don't always fill up but instead put a $20in which gets me like 5 gallons which is good for like 120 miles.

[djwimbo]

If you read the gauge cluster it says Unleaded Fuel Only. European stations and probably Brazilian ones still have Leaded gasoline and cars are meant to run it.

BTW. USA is 111th in the world in respect to most expensive gasoline. It's still cheap here compared to other countries compared to their wages.

I feel like I go through gas real fast is because I don't always fill up but instead put a $20in which gets me like 5 gallons which is good for like 120 miles.

Just b/c we're 111th in line for the most expensive fuel, doesn't mean I'm going to fill up with a smile.
I'm going to be getting W/M inj soon, so that I can run 89oct more frequently. Normally I only use it when I'll use ALL of it on the highway. NTM on 93oct I get 27-28mpg @ the posted speed limit, versus 89oct I got 32.66mpg.

your buddy has no clue what he's talking about if he claims he switched from 94 oct to e85 with no tuning.

switching from gasoline to e85 requires about 40% more fuel to maintain the same lambda reading as gasoline...been there done that

I'm not disagreeing with you, I just watched him do it, that's all.
I told him to get it tuned, but he said something along the lines of "It's alright, it was tuned rich in the first place. It's a DSM too, what's the worst that'll happen?"

[onemoremile]

Well the more ethanol you run in the tank the leaner the car is going to be. Did you log the car at all when you did this or check to see what your fuel trim readings are on block 032?


It might have cost you less money to fill the tank up but since you need to burn more of that fuel to stay at the correct AFR you will just end up burning thru that tank of fuel quicker.

I very rarely go WOT and I'm not at all worried about running a bit lean when pulling away from a stop at 0-5psi. I've never logged anything on any car. Up to a point, lean is a good thing while cruising. I wouldn't run this mix on this tune (conservative Neuspeed 15-17 psi K04) at the track - that would just be reckless.

As I mentioned, my mpg was average. I expected it to go down 10-20% but it didn't.

[onemoremile]

Umm just an FYI, ethanol is not used in Avgas100LL and for a plane to run on E85 the entire fuel system must be brought up 2 spec due to the good risk of erosion of fuel lines and O-rings.

Umm just an FYI, no wings on this ride.

[onemoremile]

If you read the gauge cluster it says Unleaded Fuel Only. European stations and probably Brazilian ones still have Leaded gasoline and cars are meant to run it.

BTW. USA is 111th in the world in respect to most expensive gasoline. It's still cheap here compared to other countries compared to their wages.

I feel like I go through gas real fast is because I don't always fill up but instead put a $20in which gets me like 5 gallons which is good for like 120 miles.

I don't understand what leaded versus unleaded has to do with anything. Do you, even for one second, think that the Audi A4 1.8t sold in Brazil was intended to run on leaded fuel? That would mean a lot of changes and throw off Audi's economy of scale. I'd bet my house that their engines are intended for unleaded fuel just like ours.

If you had two items to pick from that were virtually identical but priced differently would you choose the more expensive one? Rather than spend $60 for a tank I spent $48 and drove just as far, well over 300 miles. I can't see how arguing economics will win your argument. Hell, I've got $800 Joseph Abboud suits bought at Norstrom's and a couple that were 50-60 from ebay and nobody can tell the difference. I certainly can't. It isn't what you spend but what you didn't that counts in the long run.

[onemoremile]

your buddy has no clue what he's talking about if he claims he switched from 94 oct to e85 with no tuning.

switching from gasoline to e85 requires about 40% more fuel to maintain the same lambda reading as gasoline...been there done that

Absolutely correct. If I'm not mistaken you were the guy talking about the Brazilians running e85 for years without issue.

[pac1085]

yeah..that was me

the reason your MPG didn't go down is because you're car is still injecting the same amount of fuel, and running lean...IMO

[mike-2ptzero]

I very rarely go WOT and I'm not at all worried about running a bit lean when pulling away from a stop at 0-5psi. I've never logged anything on any car. Up to a point, lean is a good thing while cruising. I wouldn't run this mix on this tune (conservative Neuspeed 15-17 psi K04) at the track - that would just be reckless.

As I mentioned, my mpg was average. I expected it to go down 10-20% but it didn't.

15:1 is good, but I dont think 18:1 or higher would be a "good" thing. The ecu can add some fuel but I dont think it will enough.


Running to lean can also cause the EGT's to get too high and our ECU doesn't have a way of watching or adjusting for that.

[onemoremile]

During cruising and idle and when not under load a car can hit crazy lean conditions.

I've heard various things about egt. Tuners say rich or lean raises egt while engine engineers (like those at Ford Romeo) say stoich has the highest egt. I don't know enough about it to comment on it myself. Those guys are talking about running cars at 1:20-30 without problems and that is Ford - hardly the most cutting edge sophisticated engines on the planet.

I do know the car ran exceptionally well. I was also very nice to it and there were no signs of detonation. I wouldn't put a mix like this in and trash it. Again, that would be reckless. If I were to do this again I'd probably do 10 gallons of 89 and 5 of e85 or something similar.

You guys make this sound like the end of the world. It's like when I tell someone that a 2 liter made 700hp and they are astonished it didn't blow up. Or when I say I ran stock suspension without any sway bars and people can't believe I didn't crash and die. If nobody tried anything new we'd all be using solutions from a few centuries ago.

[legionvr6]

i've been wondering about e85. and how extensive the moding would need to be to at least run say 10 gallons of 91 and 5 of e85 = about 95 octain. does any one actualy have a decent amount of first hand experience?

[Wizard-of-OD]

becareful with those rubber fuel lines.
Otherwise good show!

[legionvr6]

so the only big deal is the fuel lines?

[erikas3]

Any more insight on this topic? I kinda want to try it when I fill up tomorrow :p

[NK2007]

There was a fuel war going on between the Western and kum and go today in brighton. Prices were at 2.93 and dropping. There were cops directing traffic and i guess they've each had 4 tankers come by just today. people were lined up around the block for it!

As for me... i drove by with my full tank of 100 oct and smiled...

[djwimbo]

Lean cruise is how GM gets mileage out of any of their vehicles. They're programmed to run 20-21:1 AFR while in "lean cruise". As long as the throttle doesn't change by more the 3% it'll stay that way for a long time.
20:1 under accel isn't good, 15:1 is not real bad. The only reason Stoichiometric (~14.7:1) is used, is for catalytic converter efficiency. If the vehicle doesn't have a Cat, 14.7:1 doesn't mean a damn thing.

[Squarrl]

If you read the gauge cluster it says Unleaded Fuel Only. European stations and probably Brazilian ones still have Leaded gasoline and cars are meant to run it.

American ones are the only ones ive seen that say Unleaded Fuel only, I havent
been to Brazil but English and Canadian ones dont say that for sure. There goes your theory.

[dmaize]

you need stainless steal fuel lines, injectors for alcohol, and a tune. and you "should" do a new fuel pump.

and ONEMOREMILE, regular gas is 15% alcohol, Premium is not, it is 100% petrol. so i dont think our RUBBER lines and gaskets where meant for it.

i say if your going to do it, do it right and upgrade, but for the record, if you like paying cheap prices at the supermarket for food than you should not support government subsidized e85, cause real soon its going to FUCK our farms. people forget that food is our number one necessity and when they pay farmers to stop growing food and start going gas we will have a shortage and food will be come a high demand commodity.

[djwimbo]

people forget that food is our number one necessity and when they pay farmers to stop growing food and start going gas we will have a shortage and food will be come a high demand commodity.

And how many people in the US need to eat less? Last I checked the divorce and obesity percentage per capita are a close race.

[Poopie]

I would think premium has the most ethanol in it to raise its oct.

[NK2007]

As far as the fuel lines go, vehicles made after 1992 have rubber hoses that are not eaten away by e85.

There is a lot of internet bs in this thread, and i suggest doing some reading on the subject.

Although this isn't the best source, here is a link to some myths.
http://www.change2e85.com/servlet/Page?template=Myths

edit: here is a much better source for information:
http://www.e85fuel.com/e85101/questions.php

People in south america have been using e85 since the 80's and they simply run a conversion kit. These kits piggyback the injector harness providing more fuel and adjust timing a little. If tuned properly, there are many cases of cars running better on e85 than regular gas.

Hopefully this helps disprove some myths!
Neill

[legionvr6]

so how bad would it be to run 15-91 and 5-e85

[Poopie]

i think your tank will overflow...you can try it though and report back =)

[legionvr6]

WTF is wrong with me LOL. 10-91 and 5-e85

[erikas3]

I also want to try running this mix. Does a mix of about $12 bucks 89 and $8 bucks e85 sound safe? I just wanna try it once since I know that this car wasn't necessarily made for it.

[1hotA4]

so how bad would it be to run 15-91 and 5-e85

Hey im with Poopie on this one.... Can we watch you stick 20 gallons of gas in your tank. That would be fun! haha

[1hotA4]

I have to wonder what this does for a car running high boost. I mean you would have to change your tune im guessing b/c the amount of Fuel consumed would be more. And with a bigger turbo and large injectors already pumping out. You probably would have to step up injectors just to meet the fuel needs for the power. I dont know, i have seen any E85 stations here in georgia yet. And i paid 4.05$ this morning for 93 at the station. =( They keep this up, and BMX prices are going to soar! haha

[1hotA4]

I have to wonder what this does for a car running high boost. I mean you would have to change your tune im guessing b/c the amount of Fuel consumed would be more. And with a bigger turbo and large injectors already pumping out. You probably would have to step up injectors just to meet the fuel needs for the power. I dont know, i haven't seen any E85 stations here in georgia yet. And i paid 4.05$ this morning for 93 at the station. =( They keep this up, and BMX prices are going to soar! haha