87 octane regular vs 89 octane 10% ethanol

captain archer · 08-24-2006, 12:41 AM

had a question. here in iowa (well at least in des moines) the ethanol blend is actually at least 6 cents per gallon cheaper than the regular 87 octance. is there perhaps some way of calculate the cost tradeoff to see if it actual is better to pay the higher price for the regular gas?

kDB · 08-24-2006, 10:09 AM

30% hit from ethanol, 10% ethanol so...
multiply regular * 0.97 and that's should be about correct.
for instance, at $2.759 for regular, unless ethanol is less than $2.67623, your prolly better off with regular. though this does not count the emissions difference.

someone correct me if i'm wrong.

captain archer · 08-25-2006, 12:06 AM

<div class='quotetop'>QUOTE(kDB @ Aug 24 2006, 09:09 AM) [snapback]308723[/snapback]</div>

Quote:

30% hit from ethanol, 10% ethanol so...
multiply regular * 0.97 and that's should be about correct.
for instance, at $2.759 for regular, unless ethanol is less than $2.67623, your prolly better off with regular. though this does not count the emissions difference.

someone correct me if i'm wrong.
[/b]

thanks kdb that helps a lot. so as prices go down here. like tonight entanol is at $2.519 and regular is $2.579 its almost worth the mpg hit to take the ethanol, but if prices go up the the spread between ethanol and regular stays the same it is worth paying more per gallon for the regular

tmorrowus · 10-19-2006, 07:50 PM

I noticed that price difference when I was driving through Iowa. It was strange for the 89 octane gas (ethanol blend) to be cheaper than the 87. I went with the 87 since the Toyota owners manual seems to say these cars run best on 87.

FL Buckeye · 10-19-2006, 08:21 PM

We were driving through IA and NE this summer. The temp in NE was 107 one day. Anyway, I tried the 89 w/ethanol cause it was cheaper. My mpg on I80 went down from 48 to 43 in just a few miles. Surprisingly, in CO the reg was only 85 and the Prius ran like a champ on it, back up to the 48's. as they say, YMMV.

eagle33199 · 10-20-2006, 08:58 AM

just make sure the ethanol blend is just E10, and NOT E85.

But like others said, you'll take a MPG hit when addind ethanol to the gas, since it doesn't contain as much energy. However, a little ethanol is apparently good for things, as it helps keep the engine and pipes, etc clean.

troe · 10-20-2006, 09:02 AM

<div class='quotetop'>QUOTE(tmorrowus @ Oct 19 2006, 06:50 PM) [snapback]335320[/snapback]</div>

Quote:

I noticed that price difference when I was driving through Iowa. It was strange for the 89 octane gas (ethanol blend) to be cheaper than the 87. I went with the 87 since the Toyota owners manual seems to say these cars run best on 87.
[/b]

I moved to Panama City several years ago from Wyoming. Most people don't know that 87 octane is the same as 85 octane at high altitude.

With the hit on E10, how can those trucks and SUV's afford to drive on E85? Just glad I traded my 15 MPG Jeep Wrangle for my Prius. My comute is a lot more enjoyable and I use 1/4 the gas to do it.

john1701a · 10-20-2006, 10:10 AM

<div class='quotetop'>QUOTE(pcflorida @ Oct 20 2006, 08:02 AM) [snapback]335487[/snapback]</div>

Quote:

how can those trucks and SUV's afford to drive on E85?[/b]

That's a somewhat redundant question, since you can ask the same to those owners about gas too.

Nonetheless, a photo like this from Minnesota helps to provide that answer...

captain archer · 10-25-2006, 01:51 AM

john, correct me if im wrong, but isn't the gas up there in the frozen north all at least 10% ethanol? am taking a trip up there this winter to visit family up in the Aitkin and Brainerd areas, wondering what mpg to expect while up there. on a side note with it in the 40s here in des moines i have noticed a serious drop in my mpg from mid 50's to like around mid to upper 40s per gallon

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08-24-2006, 12:41 AM	#1
captain archer Join Date: Jul 2006 Posts: 25 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	had a question. here in iowa (well at least in des moines) the ethanol blend is actually at least 6 cents per gallon cheaper than the regular 87 octance. is there perhaps some way of calculate the cost tradeoff to see if it actual is better to pay the higher price for the regular gas?

08-24-2006, 10:09 AM	#2
kDB Join Date: Jun 2005 Location: Fenton, MO Posts: 243 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	30% hit from ethanol, 10% ethanol so... multiply regular * 0.97 and that's should be about correct. for instance, at $2.759 for regular, unless ethanol is less than $2.67623, your prolly better off with regular. though this does not count the emissions difference. someone correct me if i'm wrong.

10-19-2006, 07:50 PM	#4
tmorrowus Senior Member Join Date: Dec 2003 Posts: 425 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	I noticed that price difference when I was driving through Iowa. It was strange for the 89 octane gas (ethanol blend) to be cheaper than the 87. I went with the 87 since the Toyota owners manual seems to say these cars run best on 87.

10-19-2006, 08:21 PM	#5
FL Buckeye Senior Member Join Date: Apr 2006 Location: WC Florida Posts: 142 My Car: 2006 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	We were driving through IA and NE this summer. The temp in NE was 107 one day. Anyway, I tried the 89 w/ethanol cause it was cheaper. My mpg on I80 went down from 48 to 43 in just a few miles. Surprisingly, in CO the reg was only 85 and the Prius ran like a champ on it, back up to the 48's. as they say, YMMV.

10-20-2006, 08:58 AM	#6
eagle33199 Platinum Member Join Date: Mar 2006 Location: Minnesota Posts: 3,724 My Car: 2006 Prius Package: #7 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	just make sure the ethanol blend is just E10, and NOT E85. But like others said, you'll take a MPG hit when addind ethanol to the gas, since it doesn't contain as much energy. However, a little ethanol is apparently good for things, as it helps keep the engine and pipes, etc clean.

10-25-2006, 01:51 AM	#9
captain archer Join Date: Jul 2006 Posts: 25 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	john, correct me if im wrong, but isn't the gas up there in the frozen north all at least 10% ethanol? am taking a trip up there this winter to visit family up in the Aitkin and Brainerd areas, wondering what mpg to expect while up there. on a side note with it in the 40s here in des moines i have noticed a serious drop in my mpg from mid 50's to like around mid to upper 40s per gallon