E15 gas

The gas light came on today, and the gas station I was at had E15. I was going to fill up with regular E10 but I noticed the gas cap said you can run up to E20. I know E15 has 2% less energy than E10, but I figured I'd run a little experiment for myself anyways to see if the engine performs differently and what the gas mileage is like. I have a 2.7L 2016 tacoma, so power output changes are a lot more dramatic than the 6 cylinder engines in my experiences, especially with 33s on there.

Anyways, based off what I've read typically 87 octane gas is good for compression ratios of 7:1 to 9:1. The 2.7L motor has a compression ratio of 10:1, how is Toyota getting away with requiring 87 octane gas if 90 octane is optimal for 10:1 compression? Second, albeit E15 having a slight increase in octane rating(88) would it by any chance make the engine run more efficiently? I'm not sure if Toyota has incorporated sensors to detect ethanol content in the gas, and if the ECU adjust ignition timing and VVTI timing based off ethanol content.

Either way, I thought it was something interesting to think about and was wondering if anyone had any legitimate answers on the topic.

 

Interesting topic for discussion. I am Subbing to learn about it.

 

I would avoid all e "enriched" gas at all costs. People have to realize that ethanol gas is not just robbing you of energy, ethanol gasoline is also very harsh o gaskets, sensors, etc. Here where i live (Alberta Republic, Canada)there are stations that sell just that, ethanol free. I have been avoiding that shit for years, i don't care ti save a few cents...i just boycott all ethanol gas !!!

 

E10 is fine to run, but not e15. I don't think these tacoma's are equipped to handle e15...at least long term.

 

I try to buy Ethanol free fuel whenever possible even if I have to pay a little more to get it. Sadly there are only 2 stations in my whole county that still offer Ethanol free.

 

Just a thing, but 87 is good to run up to 10.5:1 as long as you are not in high elevations.

I believe the 3.5l is 11:8. It retards the timing to run it. Same with Mazdas that have gone over 14:1.

 

At least the 3.5l engine does not come with an ethanol sensor like flex fuel Fords. Running higher ethanol fuel will impact mpg so though its cheaper (most times), you burn more of it as you literally get less bang for your buck. The fuel and power maps are not calibrated to handle the additional alcomahol.

 

I've been running nothing but E10 for twenty years (pure gasoline is not sold for road vehicles in the state I live in ) and have hundreds of thousands of miles with zero fueling issues. What you are saying is true for some older lawn equipment but not for any vehicles manufactured in the last decade or two. One nice thing about Ethanol (especially E85) is the nice power boost it can provide for some engines.

 

Nice thing about the ethanol sensors is the power boost they give the engine when something like E85 is detected. For example: Ford rated the 5.0 in the F-150 at 360 hp on pure gasoline and 375 hp when the sensors detect it is on the corn juice.

You are right about the mileage though...it drops off a cliff running E85 but not so much on E10

 

Where I am, the only fuel that ethanol-free is premium and at $1.25/litre+ (about $4.85/US gallon), no chance I'm putting that liquid gold in my tank. My last two vehicles required premium so getting to put 87 in has been a nice break on the wallet. I just make sure I'm always using Top Tier fuel and none of that discount station crap.

 

I agree and have not had a fuel related problem, but I still find that ethanol in fuel is just dumb. Use that corn for food or drinking. It is ridiculous to burn it.

 

Same here in connecticut...before that we had mtbe blended in our gasoline till they found tanks that leaked it into water supplys caused cancer. I drove my 01 tundra nearly 300k miles mostly running e10. Imo, our state really doesn't need it.

 

I go back and forth from E10 to E15 in my 4runner, and previously in my '15 Taco. I have never noticed any measurable change in fuel economy or performance. I believe modern engines are designed to run on ethanol blended fuel. Even in my previous 4runner, I would occasionally fill up with ethanol free fuel when available, and never gained anything.

That said, I do try to avoid using ethanol fuel in anything that tends to sit unused for prolonged periods of time, such as my boat, chainsaw, etc.

 

Oddly, in m bike, I filled half a tank of E0 (same 87 octane) and noticed a difference just rolling away from the pump. That tank had more power, a deeper exhaust note, and better MPGs. I never had the opportunity to test this with our cars.

 

A smaller motor might be more sensitive.

I can't imagine fuel changing the exhaust note, unless the computer adjusted timing to adjust for the different fuel. Seems weird.

Newer bike? Or older?

 

Good point.

It is on the smaller side, 916cc. It's a 2001 with a dead nuts simple open loop EFI. Still, getting 41mpg while having a fun commute and going up from there on long rides. Not bad at all for a sporttourer.

The exhaust note didn't really surprise me. More boom per ignition?

My friend filled his newer H-D with an electronic throttle at the same time and reported similar results.


I have been wanting to see if I could repeat the experience with either the bike or the Taco, esp since I'm tuned, to verify. I just haven't been through that area since.

 

"Ethanol contains about one-third less energy than gasoline. So, vehicles will typically go 3% to 4% fewer miles per gallon on E10 and 4% to 5% fewer on E15 than on 100% gasoline" - Source: https://bit.ly/3eOUpXE

"Pure gasoline produces more than 116,000 BTU of heat per gallon. With ethanol, we produce 76,330 BTU per gallon. We produce 33% less energy, so it takes more gallons to power a vehicle. With E-10 or 10% ethanol, mileage will normally drop more than 3%. As the percentage of ethanol increases the drop in mileage gets worse." - Source: https://bit.ly/3hvkWv9

https://www.buyrealgas.com/

https://www.pure-gas.org

Ed

 

Corn country around here, also a local ethanol plant - most of us know better than to use it in anything but a rental car or something tuned that is more than likely putting big power to the pavement

I've always run supreme ethanol free 91 octane in all of my Yotas. They still get crap for mileage due to a heavy right foot but I certainly never listen to them knock.

 

I’m just curious, did you read the post at all?

 

LOL, OK. I'll make sure to tell my previous 4runner with nearly 260K on E10. Still ran perfect, BTW.