What grade of gas do you pump?

Presto · 03-18-2006, 07:51 AM

Wow... I sure don't want that kind of mechanic working on my car if they don't even know anything about what kind of octane gas to put in the car. My last car demanded 91 (2k3 Sentra Spec-V). I could put in lower octane, but then the anti-knock sensor would turn down the timing and I'd get crappy performance. I'm glad the Prius uses regular gas. I fill up half as much and pay around 40-50 cents less per gallon.

OverTork · 03-18-2006, 08:21 AM

It may be that he uses premium gas gas not for the higher octane but for the added detergent. Several gas companies tout their premium as purer and having enhaced detergent content. If you use a Top Tier brand you can get the benefit of the extra cleaners without having to buy the more expensive premium grade.

jw_teacher · 03-18-2006, 11:29 AM

A higher grade of ocatane simply allows higher compression before combustion. Fast cars need a high octane rating because of their piston's large compression ratio. For example, an octane rating of 93 would mean the other 7 percent mix would be hectane. If there was a higher percentage mix of hectane in the fuel, it would ignite prematurely in the cylinder heads during compression (called "knocking") and cause damage.

Hectane, the 13% grade you find mixed with an octane rating of 87 is all that is needed for any conventional car (including the Prius) to prevent premature ignition. Having a higher grade of octane in the Prius does not give any sort of benefit to the longitivity of the engine or boost power/increase mileage. The only thing it does is take more money out of your pocket.

jw_teacher · 03-18-2006, 11:34 AM

Quote:

Originally posted by windstrings@Mar 18 2006, 02:12 AM
Yep.. higher octane is actually a little "less" explosive... you may even get "worse" gas mileage!

[snapback]226369[/snapback]

It is less explosive under compression but the spark plugs are the only thing that ignites the fuel in a petrol-powered motor (and if it isn't you're in trouble).

Gas mileage will have zero effect whether it is 87 or any other higher grade.

Walker1 · 03-18-2006, 12:00 PM

I use 87 octane in my Prius, Honda Accord, 1988 Ford mini van, and 93 in my Harley. HD calls for at least 91 in the 1200 CC engine.

darelldd · 03-18-2006, 01:53 PM

Quote:

Originally posted by tripp@Mar 17 2006, 08:19 PM
My understanding is that using an "over" rated octane fuel is bad for the emissions system. I know I read that somewhere. Can someone confirm or deny?

[snapback]226308[/snapback]

I can't say if it is bad for the emissions system, but it will pollute more, as the octane additives do not burn as well as the gasoline. Might not be measurable, but it IS more pollution.

In CA, the same detergents must be used in all grades of gasoline sold (we had a lawsuit about that maybe eight years ago) - so at least here in CA, there's ZERO reason to use a higher-grade gas than one that does not ping. If the car doesn't ping on the lowest octane, the lowest octane is what you should use.

cmwade77 · 03-18-2006, 02:03 PM

Quote:

Originally posted by darelldd@Mar 18 2006, 11:53 AM
I can't say if it is bad for the emissions system, but it will pollute more, as the octane additives do not burn as well as the gasoline. Might not be measurable, but it IS more pollution.

In CA, the same detergents must be used in all grades of gasoline sold (we had a lawsuit about that maybe eight years ago) - so at least here in CA, there's ZERO reason to use a higher-grade gas than one that does not ping. If the car doesn't ping on the lowest octane, the lowest octane is what you should use.

[snapback]226545[/snapback]

Can someone confirm that the same degertents must be used in all grades of gas in California? Perhaps via a link to the lawsuit, because Shell claims that the V-Power is only in the Premium and I am hewre in California.

Frank Hudon · 03-18-2006, 02:27 PM

compression ration of 13 to 1 only occures under very light load where as the high load is at 8 to 1 so only low octane is need to control detonation. Also the 1NZ-FXE engine is equipped with a knock sensor that will retard the timing if need to control any detonation that it hears.

joeh4 · 03-18-2006, 02:49 PM

Quote:

Originally posted by galaxee@Mar 17 2006, 10:20 PM
okay. time to break this out again.

from the toyota hybrid system diagnosis training manual... page 3-4, top paragraph:

"OCTANE RATING
At a minimum the gasoline used should meet the specifications of ASTM D4814 in the United States. For the Prius, use only UNLEADED gasoline with an octane rating of 87.

NOTE: Do not use premium gasoline. It may cause starting problems with the Prius. There is no gas mileage benefit when using premium gas!"

[snapback]226276[/snapback]

galaxee,

I pick up my 2006 Red Barcelona Prius Monday after waiting for almost 7 months.

I downloaded a 2004 manual from a generous PriusChat member just last week and have been reading through it. Just last night under "Gas" (I don't remember what page because it printed out 318 pages, but about page 190 under my print out) it says specifically to use "octane 87 or R.O.N. 93, or 'higher'". I don't know what they meant by R.O.N. 93.

I have been concerned on this matter because I went to 4 local gas stations and all have regular at 89 octane (Shell, Phillips 66, Citgo & Hucks). All are close to me. I did find a BP with octane 87 but I rarely go there because they are not listed as "Top Tier" and are not open all night, nor are they conviently located and I usual fill up after work (2nd shift).

Everything I had read and searched for prior to this on PriusChat since becoming a member about 3 weeks ago said Octance 87 and so does "john1017a's site". Does anyone know if the 2006 Manual recommend Octane 87 or "higher"?

Thanks!

joe

darelldd · 03-18-2006, 03:47 PM

Quote:

Originally posted by cmwade77@Mar 18 2006, 11:03 AM
Can someone confirm that the same degertents must be used in all grades of gas in California? Perhaps via a link to the lawsuit, because Shell claims that the V-Power is only in the Premium and I am hewre in California.

[snapback]226549[/snapback]

Hmm. I'll take a look. It was Unocal that got spanked on this at the time... and I know that all of *their* stuff has the same detergents.

Good to be skeptical! Maybe it was ONLY Unocal? I'll poke around. I had a friend involved in the lawsuit.

Anybody know what "V-Power" actually is? if it is just a marketing slogan, then they may very well only offer it in the "premium" grade.

View Poll Results: What grade of gas do you pump?
I pump 87	160	91.43%
I pump 89	10	5.71%
I pump 93	5	2.86%
Who cares!	0	0%
Voters: 175. You may not vote on this poll

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
What grade gasoline do you use	priussoris	Fuel Economy	43	10-05-2007 05:31 PM
Alleged Actual Answers to Sixth Grade History tests	larkinmj	Fred's House of Pancakes	7	06-28-2006 09:18 AM
Fuel Grade Prices	hycamguy07	Fred's House of Pancakes	2	03-31-2006 03:05 AM
What grade of fuel works best for you?	HAMMER55	Prius Main Forum	26	11-05-2005 11:29 AM
Can the Prius handle the Sunol Grade?	rwithop	CA - San Francisco Bay Area	6	05-17-2005 01:20 AM

03-18-2006, 07:51 AM	#21
Presto Has his homepage set to PC Join Date: Mar 2005 Location: Vancouver, BC Posts: 1,159 My Car: 2005 Prius Package: B Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 3	Wow... I sure don't want that kind of mechanic working on my car if they don't even know anything about what kind of octane gas to put in the car. My last car demanded 91 (2k3 Sentra Spec-V). I could put in lower octane, but then the anti-knock sensor would turn down the timing and I'd get crappy performance. I'm glad the Prius uses regular gas. I fill up half as much and pay around 40-50 cents less per gallon.

03-18-2006, 08:21 AM	#22
OverTork Member Join Date: Jun 2005 Location: Northville, MI Posts: 65 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	It may be that he uses premium gas gas not for the higher octane but for the added detergent. Several gas companies tout their premium as purer and having enhaced detergent content. If you use a Top Tier brand you can get the benefit of the extra cleaners without having to buy the more expensive premium grade.

03-18-2006, 11:29 AM	#23
jw_teacher Join Date: Sep 2005 Location: Saint Charles, MO Posts: 65 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	A higher grade of ocatane simply allows higher compression before combustion. Fast cars need a high octane rating because of their piston's large compression ratio. For example, an octane rating of 93 would mean the other 7 percent mix would be hectane. If there was a higher percentage mix of hectane in the fuel, it would ignite prematurely in the cylinder heads during compression (called "knocking") and cause damage. Hectane, the 13% grade you find mixed with an octane rating of 87 is all that is needed for any conventional car (including the Prius) to prevent premature ignition. Having a higher grade of octane in the Prius does not give any sort of benefit to the longitivity of the engine or boost power/increase mileage. The only thing it does is take more money out of your pocket.

03-18-2006, 12:00 PM	#25
Walker1 Senior Member Join Date: Jan 2006 Location: FL Posts: 882 My Car: 2008 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	I use 87 octane in my Prius, Honda Accord, 1988 Ford mini van, and 93 in my Harley. HD calls for at least 91 in the 1200 CC engine.

03-18-2006, 02:27 PM	#28
Frank Hudon Senior Member Join Date: Jan 2004 Posts: 4,144 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	compression ration of 13 to 1 only occures under very light load where as the high load is at 8 to 1 so only low octane is need to control detonation. Also the 1NZ-FXE engine is equipped with a knock sensor that will retard the timing if need to control any detonation that it hears.