Ethanol free pump gas vs pump gas with 10-15% ethanol debate... please chime in!
01-07-2019, 02:33 PM
#1
Ethanol free pump gas vs pump gas with 10-15% ethanol debate... please chime in! This thread I want to strictly stick with gasoline you buy at a gas station. Not E85. Not gas you buy in a drum from VP or other race fuel companies. Strictly pump gas that has ethanol mixed in or ethanol free.
Mainly let’s focus on horsepower but other thing such as mileage as well.
Obviously when I talk about mixed gas with ethanol I mean
the gas you buy at the pump that’s mixed... not you mixing it.
So which in your opinion is better for horsepower? Ethanol free 93 or gas with 10-15% ethanol? I had a tuner tell me not to run my ls1 on any mixed gas, just strictly ethanol free if I wanted the max performance out of his tune. His reasoning was he’s seen cars with 10% ethanol knock at higher rpm and we all know what our computers do when knock is sensed.
I am not a tuner so I’m interested in what you guys have to say and experienced.
I will say say this was a tune on my car back when I first bought it in 2014. 2000 Z28 all stock. I put a slp cai and Kooks headers and true duals.
Later her when I went with a built trans, 4K stall, and S60 with 4.10s I had another guy tune it who’s well known on here for mail order tunes. He said that tune was an absolute mess from the other guy. I noticed afterwards the car did run better.
I have noticed on my other vehicles that I get better mileage using ethanol free gas. I’ve done several tests on my 2009 Malibu and 2016 F150 (5.0) and both see an improvement of 1.5-2 mugs with ethanol free. Interstate driving is a touch better.
Interested in in your opinions...
Mainly let’s focus on horsepower but other thing such as mileage as well.
Obviously when I talk about mixed gas with ethanol I mean
the gas you buy at the pump that’s mixed... not you mixing it.
So which in your opinion is better for horsepower? Ethanol free 93 or gas with 10-15% ethanol? I had a tuner tell me not to run my ls1 on any mixed gas, just strictly ethanol free if I wanted the max performance out of his tune. His reasoning was he’s seen cars with 10% ethanol knock at higher rpm and we all know what our computers do when knock is sensed.
I am not a tuner so I’m interested in what you guys have to say and experienced.
I will say say this was a tune on my car back when I first bought it in 2014. 2000 Z28 all stock. I put a slp cai and Kooks headers and true duals.
Later her when I went with a built trans, 4K stall, and S60 with 4.10s I had another guy tune it who’s well known on here for mail order tunes. He said that tune was an absolute mess from the other guy. I noticed afterwards the car did run better.
I have noticed on my other vehicles that I get better mileage using ethanol free gas. I’ve done several tests on my 2009 Malibu and 2016 F150 (5.0) and both see an improvement of 1.5-2 mugs with ethanol free. Interstate driving is a touch better.
Interested in in your opinions...
01-07-2019, 03:39 PM
#2
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Ethanol is toxic, caustic and corrosive. Many vehicles in the last twenty years or so can use E-10 because they were made with materials that can withstand it. Older cars should NEVER use it as it can corrode anything it touches, gas tank, carb, fuel lines fuel injection, and so on. Even on new cars you don't want to spill it on your paint while you fill your tank. It also goes bad within a few weeks or months so you don't want to leave a car parked with a tankful for any length of time. It doesn't blend with gasoline permanently and will eventually fall out of suspension with the gas. It also attracts and absorbs water, so if you use it in humid areas it's a problem. I worked for a car dealer twenty years ago and the shop regularly got little old ladies' cars in that weren't driven much and wouldn't run- bad gas was all they could figure, not knowing at the time that the only bad gas was the E10 that not a lot of people used back then. It gummed up the carbs and fi and gas tank and everything in between.
Since ethanol makes much less energy than gasoline, it gets poorer fuel mileage, even at a ten percent mix. The only good thing about it is it makes a good racing fuel as it's more resistant to burning (higher octane) so higher compression can be used, and since race engines don't last long anyway, all the negatives don't matter.
Since ethanol makes much less energy than gasoline, it gets poorer fuel mileage, even at a ten percent mix. The only good thing about it is it makes a good racing fuel as it's more resistant to burning (higher octane) so higher compression can be used, and since race engines don't last long anyway, all the negatives don't matter.
01-07-2019, 03:42 PM
#3
TECH Senior Member
I wish we in California had the choice. Anything we buy is required to have ethanol in it. Straight gas is unobtainium.
01-07-2019, 03:50 PM
#4
TECH Addict
I hear all the horror stories but have never had an issue with anything outside of lawnmowers and two strokes. I’ve had my cars sit for extended times and they seem to run fine but I won’t beat on them until I get a take or two through them.
For power, I’ve never compared but if e85 is better than straight 93 it leads me to believe e10 is also better just not as much. ¯\_(ツ)_/¯
For power, I’ve never compared but if e85 is better than straight 93 it leads me to believe e10 is also better just not as much. ¯\_(ツ)_/¯
01-09-2019, 01:29 PM
#6
01-10-2019, 11:36 AM
#7
The big problem is that having ethanol in your gas just allows the gas companies to use a crappier octane fuel as the base so the octane level stays the same when comparing 91 octane 0% ethanol to 91 octane 10% ethanol. Your gas mileage just takes a few percent hit with no real performance benefit at those low ethanol percentages.
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01-11-2019, 02:31 AM
#8
As Oange and Nic D have brought to light, the OP's question is flawed. Given "all else equal", any amount of ethanol will be better for power, simply because it carries its own oxygen. The same is true for nitromethane or methanol. The downside is that ethanol (or other oxygen carrying fuels) need more flow to fuel any given horsepower. In a pump gas situation, ethanol is never added to good gas to make it produce more power, but rather added to **** gas to improve detonation resistance. (and also to placate farm subsidies in a political rant I won't get into here)
01-11-2019, 04:16 AM
#9
The BTU's of ethanol are 50% of Gasoline.
Up here in Canada we have Sunoco 94 with 10% ethanol or straight 91 at Shell,Esso,Mobil ect.
There are a few Esso stations around Toronto that have straight 93 gas.
When 93 was available around here I did some comparisons at the drag strip and found the 93 to be slightly quicker than the 94 blend.
The 94 blend is quicker than the 91 at the strip but the 91 returns better fuel economy per tank in everyday driving.
Up here in Canada we have Sunoco 94 with 10% ethanol or straight 91 at Shell,Esso,Mobil ect.
There are a few Esso stations around Toronto that have straight 93 gas.
When 93 was available around here I did some comparisons at the drag strip and found the 93 to be slightly quicker than the 94 blend.
The 94 blend is quicker than the 91 at the strip but the 91 returns better fuel economy per tank in everyday driving.
01-11-2019, 01:24 PM
#10
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I agree.
Ethanol is toxic, caustic and corrosive. Many vehicles in the last twenty years or so can use E-10 because they were made with materials that can withstand it. Older cars should NEVER use it as it can corrode anything it touches, gas tank, carb, fuel lines fuel injection, and so on. Even on new cars you don't want to spill it on your paint while you fill your tank. It also goes bad within a few weeks or months so you don't want to leave a car parked with a tankful for any length of time. It doesn't blend with gasoline permanently and will eventually fall out of suspension with the gas. It also attracts and absorbs water, so if you use it in humid areas it's a problem. I worked for a car dealer twenty years ago and the shop regularly got little old ladies' cars in that weren't driven much and wouldn't run- bad gas was all they could figure, not knowing at the time that the only bad gas was the E10 that not a lot of people used back then. It gummed up the carbs and fi and gas tank and everything in between.
The above has not been consistent with my personal experience over the last couple of decades with my garage queens. I'm sure there are folks who've seen issues, otherwise there would be no "horror stories" to go around, but these issues are not a given.
I've used nothing but E10 fuel in my '71 for the last 10+ years of which I've owned it. The tank appears to still be original, so is the sender (I assume, and it still works fine). The pump and rubber sections of fuel line are mostly from the early '90s when it was last restored, all working just fine. The old Holley 4160 carb hasn't been rebuilt since I installed it back in '08, and every time I've opened it up for tuning adjustments it has looked perfect inside. No issues at all. And that's exclusively with E10 fuel in a car that mostly sits in my garage, it gets maybe 2-3 tanks of gas per year at most so the fuel is often several months old. It sits every winter with the same gas for usually 6 months. After a decade of all this, no issues at all.
My '98 still has a 100% original fuel system, nothing has ever been replaced other than the fuel filter (as basic maintenance, not due to any clog or actual problem). It's always been fed E10 fuel, and this has caused no issues at all. I drive this one even less than my '71, it usually only gets one tank of fuel per year - so the gas is sometimes nearly 12 months old. At 20 years old (15 years under my ownership), there are no driveability issues, no leaks, nothing broken.
In fairness, I do use Stabil and Red Line SI-1 treatment for both vehicles in every tank as they both sit so often. And I keep the tanks full during extended storage periods (such as winter). But those are the only precautions I've ever taken, and I've never seen any of the ethanol "horror stories" surface with either vehicle after all these years of the same routine.
01-12-2019, 08:07 AM
#11
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Just about the same here, so I don't worry about it. Life is way too short, just fill your tank and go. I've seen no ill effects in our DDs from using it either. Our current mileage is 150ish, 180ish, and 200ish, all vehicles run like brand new. Camaro sits with E85 in it and I only start it about once a month. So far so good since i E swapped it a year ago.
01-12-2019, 08:20 AM
#12
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The only "horror" stories I have seen with Ethanol, are in the marine industry. Ethanol-gas blends have been wrecking havoc on the marine industry for years. Boat and motor manufacturers have learned how to "deal" with Ethanol though. The newer boats/motors are running on Ethanol just fine.
It started with the fuel lines collapsing. The old rubber fuel lines were breaking down from the alcohol content in the fuel. That caused engines to starve for fuel. In some cases, pieces of the fuel line were sucked into the engine, and clogged injectors. Cars don't have that problem, because they use stainless steel.
The other common problem was from engines running hot and burning holes in the block/heads/pistons. They already run on the ragged edge, and they weren't tuned for Ethanol. The new engines are tuned for Ethanol blends, and do just fine.
The only "problem" I have experienced with Ethanol-blends, is a decrease in fuel mileage.
It started with the fuel lines collapsing. The old rubber fuel lines were breaking down from the alcohol content in the fuel. That caused engines to starve for fuel. In some cases, pieces of the fuel line were sucked into the engine, and clogged injectors. Cars don't have that problem, because they use stainless steel.
The other common problem was from engines running hot and burning holes in the block/heads/pistons. They already run on the ragged edge, and they weren't tuned for Ethanol. The new engines are tuned for Ethanol blends, and do just fine.
The only "problem" I have experienced with Ethanol-blends, is a decrease in fuel mileage.
01-12-2019, 10:35 AM
#13
TECH Senior Member
It's not so much that our engines are tuned for anything, it's that they can tune themselves for anything. The O2 sensors take care of that. The A/F ratio is maintained no matter what swill goes thru our engines.
01-12-2019, 11:15 AM
#14
That number is to high. Around +- 40% depending on purity.
Gasoline to e85 tune usually requires adding 32%-38% more fuel but every engine I've tuned responds differently.
Here's something that I always find comical, Some people vow to never put E-fuel in the cars but will spend $4 for a bottle of HEET gas treatment and dump it in the tank.... HEET is 99% Isopropanol alcohol! HEET MSDS
Gasoline to e85 tune usually requires adding 32%-38% more fuel but every engine I've tuned responds differently.
Here's something that I always find comical, Some people vow to never put E-fuel in the cars but will spend $4 for a bottle of HEET gas treatment and dump it in the tank.... HEET is 99% Isopropanol alcohol! HEET MSDS
01-12-2019, 11:18 AM
#15
Ethanol is toxic, caustic and corrosive. Many vehicles in the last twenty years or so can use E-10 because they were made with materials that can withstand it. Older cars should NEVER use it as it can corrode anything it touches, gas tank, carb, fuel lines fuel injection, and so on. Even on new cars you don't want to spill it on your paint while you fill your tank. It also goes bad within a few weeks or months so you don't want to leave a car parked with a tankful for any length of time. It doesn't blend with gasoline permanently and will eventually fall out of suspension with the gas. It also attracts and absorbs water, so if you use it in humid areas it's a problem. I worked for a car dealer twenty years ago and the shop regularly got little old ladies' cars in that weren't driven much and wouldn't run- bad gas was all they could figure, not knowing at the time that the only bad gas was the E10 that not a lot of people used back then. It gummed up the carbs and fi and gas tank and everything in between.
Since ethanol makes much less energy than gasoline, it gets poorer fuel mileage, even at a ten percent mix. The only good thing about it is it makes a good racing fuel as it's more resistant to burning (higher octane) so higher compression can be used, and since race engines don't last long anyway, all the negatives don't matter.
Since ethanol makes much less energy than gasoline, it gets poorer fuel mileage, even at a ten percent mix. The only good thing about it is it makes a good racing fuel as it's more resistant to burning (higher octane) so higher compression can be used, and since race engines don't last long anyway, all the negatives don't matter.
01-12-2019, 02:36 PM
#16
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It started with the fuel lines collapsing. The old rubber fuel lines were breaking down from the alcohol content in the fuel. That caused engines to starve for fuel. In some cases, pieces of the fuel line were sucked into the engine, and clogged injectors. Cars don't have that problem, because they use stainless steel.
01-20-2019, 12:02 AM
#17
Ethanol sucks, fuel from the air. I put a video on youtube of it sucking in moisture in under 5 minutes. You can leave straight gas out for days. Boats had fuel line issue, fiberglass fuel tank issue, and carb issues. Holley 4150 carbs will have the bowl coatings break off from the fuel, seen it many times. E98 stinks, we need to add scented top end lube to the drag car soon, yuck. I'm actually glad that the word is all this flex fuel crap is going away in the states.
01-20-2019, 12:22 AM
#18
TECH Senior Member
Man, I hope you're right! BUT I haven't heard anything about it. The corn lobby is too strong in this country to get rid of ethanol anytime soon. But yeah I would love to be able to get alky-free gas.