Premium Unleaded?
01-04-2001, 03:55 PM
#1
8th Gear
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Premium Unleaded?
I know this may sound kind of dumb...but here it goes:
With all this talk about gas mileage, no one has mentioned what they pay for their gas; nor what type of gas they use.
The book recommends Premium 91 Octane or better (and that's all I've ever used). Has anyone ever tried a lower octane Fuel in their Type-S?
Here in Dallas 91 Octane runs about $1.55, and I average about 21 MPG.
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Red CL Type-S
[This message has been edited by Eric the Red (edited 01-04-2001).]
With all this talk about gas mileage, no one has mentioned what they pay for their gas; nor what type of gas they use.
The book recommends Premium 91 Octane or better (and that's all I've ever used). Has anyone ever tried a lower octane Fuel in their Type-S?
Here in Dallas 91 Octane runs about $1.55, and I average about 21 MPG.
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Red CL Type-S
[This message has been edited by Eric the Red (edited 01-04-2001).]
01-04-2001, 04:03 PM
#2
The Creator
All I know is that I always use Mobil 93 octane...
Have no idea what I pay or what MPG I get. Math ain't my subject
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2001 Acura 3.2 CL Type-S
San Marino Red (Navigation)
PIAA 19173 Ion Yellow Fog Lights
Aftermarket Black Wood Trim Kit
Have no idea what I pay or what MPG I get. Math ain't my subject
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2001 Acura 3.2 CL Type-S
San Marino Red (Navigation)
PIAA 19173 Ion Yellow Fog Lights
Aftermarket Black Wood Trim Kit
01-04-2001, 04:27 PM
#3
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Same here Soopa. I get Sunoco 93 (they don't have 91, at least not where I go). I never pay attention to price.
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2001 Acura 3.2 CL Type-S
San Marino Red / Parchment
non-nav - wheel locks - splash guards
#26519
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2001 Acura 3.2 CL Type-S
San Marino Red / Parchment
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#26519
01-04-2001, 04:30 PM
#4
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<font face="Verdana, Arial" size="2">Originally posted by Eric the Red:
I know this may sound kind of dumb...but here it goes:
The book recommends Premium 91 Octane or better (and that's all I've ever used). Has anyone ever tried a lower octane Fuel in their Type-S?
</font>
I know this may sound kind of dumb...but here it goes:
The book recommends Premium 91 Octane or better (and that's all I've ever used). Has anyone ever tried a lower octane Fuel in their Type-S?
</font>
If they recommend high-octane, use it. The benefit of higher octanes is higher compressibility, (and not "cleaner" burning as many people think). The new CL's have engines with high compression ratios. A lower octane gasoline will self-detonate under compression before the piston reaches the top of its stroke and the plug fires. This will cause engine knock, severe wear on the engine, and emissions higher in pollutants due to incomplete combustion.
Using High octane gas in an engine that doesn't call for it has no benefits, but in the case of the New CL's, use it.
UDMechE
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'99 2.3CL 5-spd. Black w/ spoiler, fogs, CD/Cass, and a CoPilot.
[This message has been edited by UDMechE (edited 01-04-2001).]
01-04-2001, 04:39 PM
#5
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I always use premium which is 92 Octane where I go. It's about $1.70/gal around here. Lately, I've had a problem with engine knock even using premium when I buy gas at Costco so I've stopped using that brand and go to regular gas stations.
My understanding of the whole octane thing is this.... if the engine does not knock, it's okay to use regardless of the octane number. The key is to use the lowest (and hence cheapest) octane available. If you're car knocks on 89 octane, then try 91. If it doesn't knock on 89 octane, then you're wasting you're money buying higher octane gas. I think Acura recommends premium because the engine is probably tuned such that it should require 91 octane or higher in order to avoid engine knock. I'll try to find the link of where I learned about all this stuff....
[This message has been edited by GoldTypeS (edited 01-04-2001).]
My understanding of the whole octane thing is this.... if the engine does not knock, it's okay to use regardless of the octane number. The key is to use the lowest (and hence cheapest) octane available. If you're car knocks on 89 octane, then try 91. If it doesn't knock on 89 octane, then you're wasting you're money buying higher octane gas. I think Acura recommends premium because the engine is probably tuned such that it should require 91 octane or higher in order to avoid engine knock. I'll try to find the link of where I learned about all this stuff....
[This message has been edited by GoldTypeS (edited 01-04-2001).]
01-04-2001, 04:39 PM
#6
<font face="Verdana, Arial" size="2">Originally posted by soopa:
(snip)...
Math ain't my subject
</font>
(snip)...
Math ain't my subject
</font>
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1998 Iced Blue CL 3.0 ** Some mods, but who cares, I want a Type-S!!
Re-Registered, back down to newbie status =(
01-04-2001, 04:41 PM
#7
I guess I should answer the question while I'm here
. I have always used Sunoco 93 octaine. Right now it's around $1.77 a gallon....------------------
1998 Iced Blue CL 3.0 ** Some mods, but who cares, I want a Type-S!!
Re-Registered, back down to newbie status =(
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01-04-2001, 04:43 PM
#8
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Here is some info on octane if interested:
This was obtained from:
http://www.seansa4page.com/resource/octane.html
And here is another link... haven't read this one yet.
http://www.nsxprime.com/FAQ/Miscella...lAdditives.htm
<font face="Verdana, Arial" size="2">
6.13 Can higher octane fuels give me more power?
On modern engines with sophisticated engine management systems, the engine can operate efficiently on fuels of a wider range of octane rating, but there remains an optimum octane for the engine under specific driving conditions. Older cars without such systems are more restricted in their choice of fuel, as the engine can not automatically adjust to accommodate lower octane fuel. Because knock is so destructive, owners of older cars must use fuel that will not knock under the most demanding conditions they encounter, and must continue to use that fuel, even if they only occasionally require the octane.
If you are already using the proper octane fuel, you will not obtain more power from higher octane fuels. The engine will be already operating at optimum settings, and a higher octane should have no effect on the management system. Your driveability and fuel economy will remain the same. The higher octane fuel costs more, so you are just throwing money away. If you are already using a fuel with an octane rating slightly below the optimum, then using a higher octane fuel will cause the engine management system to move to the optimum settings, possibly resulting in both increased power and improved fuel economy. You may be able to change octanes between seasons ( reduce octane in winter ) to obtain the most cost-effective fuel without loss of driveability.
Once you have identified the fuel that keeps the engine at optimum settings, there is no advantage in moving to an even higher octane fuel. The manufacturer's recommendation is conservative, so you may be able to carefully reduce the fuel octane. The penalty for getting it badly wrong, and not realising that you have, could be expensive engine damage.</font>
6.13 Can higher octane fuels give me more power?
On modern engines with sophisticated engine management systems, the engine can operate efficiently on fuels of a wider range of octane rating, but there remains an optimum octane for the engine under specific driving conditions. Older cars without such systems are more restricted in their choice of fuel, as the engine can not automatically adjust to accommodate lower octane fuel. Because knock is so destructive, owners of older cars must use fuel that will not knock under the most demanding conditions they encounter, and must continue to use that fuel, even if they only occasionally require the octane.
If you are already using the proper octane fuel, you will not obtain more power from higher octane fuels. The engine will be already operating at optimum settings, and a higher octane should have no effect on the management system. Your driveability and fuel economy will remain the same. The higher octane fuel costs more, so you are just throwing money away. If you are already using a fuel with an octane rating slightly below the optimum, then using a higher octane fuel will cause the engine management system to move to the optimum settings, possibly resulting in both increased power and improved fuel economy. You may be able to change octanes between seasons ( reduce octane in winter ) to obtain the most cost-effective fuel without loss of driveability.
Once you have identified the fuel that keeps the engine at optimum settings, there is no advantage in moving to an even higher octane fuel. The manufacturer's recommendation is conservative, so you may be able to carefully reduce the fuel octane. The penalty for getting it badly wrong, and not realising that you have, could be expensive engine damage.</font>
http://www.seansa4page.com/resource/octane.html
And here is another link... haven't read this one yet.
http://www.nsxprime.com/FAQ/Miscella...lAdditives.htm
01-04-2001, 04:49 PM
#9
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The key point though is that knock is destructive to the engine.
The knocking sound you hear is the self-detonation of the air/fuel mixture under compression before the spark plug fires, thus pushing down on an upward traveling piston.
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'99 2.3CL 5-spd. Black w/ spoiler, fogs, CD/Cass, and a CoPilot.
The knocking sound you hear is the self-detonation of the air/fuel mixture under compression before the spark plug fires, thus pushing down on an upward traveling piston.
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'99 2.3CL 5-spd. Black w/ spoiler, fogs, CD/Cass, and a CoPilot.
01-04-2001, 05:08 PM
#10
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I use Texaco 93 octane only. Last night when I filled up it was $1.59 / gallon.
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avengerjr
2001 CL-S Satin Silver
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"hockey + music + cars = life"
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avengerjr
2001 CL-S Satin Silver
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01-04-2001, 05:43 PM
#11
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I use Exxon 93 and have never had a problem with it. The last time I filled up it was around $1.65 per gallon.
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2001 Acura CL-S
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2001 Acura CL-S
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01-04-2001, 06:10 PM
#12
ACME sucks!
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I've been using 93 octane since I bought the car and had a few knocks for a while, likely from using 'cheap' gas from my local 7-11. I have been using only Mobil, Exxon, Shell, and Texaco for the last 3 months and no problems. I average 20 mpg in the city and 27 on the highway, but could get better if I'd slow down some. I usually pay about $1.55 a gallon.
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2001 Acura CL-S
Satin Silver/Ebony
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Still trying to find a K&N filter!
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2001 Acura CL-S
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Wheel Locks
Tint
Splash Guards
PIAA Bulbs
Still trying to find a K&N filter!
01-04-2001, 06:52 PM
#13
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Hmm maybe I should switch to Mobil/Exxon 93 after using Arco crap
I hear slight knocks/thumps during startup
1) Can this also be dirt/crap deposits at the station's pump that causes knocks?
2) How about cold engines..i.e. havn't used the car in a day or two?
Regardless, my CL-P is now getting
near 30 miles per gallon hwy {ahahahahha} and low 20s for city using 76's 92. Luv it!
Havn't disengaged TCS yet (similar to VSA on CL-S)
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- Kvit -
2001 CL-P Blue Sub 6
*Polarg BlHybrid M-6 Road lamps
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http://albums.photopoint.com/j/Album...725&a=10358832
I hear slight knocks/thumps during startup
1) Can this also be dirt/crap deposits at the station's pump that causes knocks?
2) How about cold engines..i.e. havn't used the car in a day or two?
Regardless, my CL-P is now getting
near 30 miles per gallon hwy {ahahahahha} and low 20s for city using 76's 92. Luv it!
Havn't disengaged TCS yet (similar to VSA on CL-S)
------------------
- Kvit -
2001 CL-P Blue Sub 6
*Polarg BlHybrid M-6 Road lamps
*Polarg BlHybrid M-14 Turning Signal/M-4 Side Markers next
http://albums.photopoint.com/j/Album...725&a=10358832
01-04-2001, 06:54 PM
#14
Cajun Gumbo Man
I am not sure that I have seen LOWER than 93 in California. WE don't want to pollute our air ! I know in TEXAS, they don't care much for the air, because I've lived there for 8 years......price is more important in Texas, not in California, because we have NO choice !
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2001 CL Type S Black/Ebony w/NAVI
1998 Accord Coupe EX-V6
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2001 CL Type S Black/Ebony w/NAVI
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01-04-2001, 06:58 PM
#15
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<font face="Verdana, Arial" size="2">Originally posted by Fabvsix:
I am not sure that I have seen LOWER than 93 in California. WE don't want to pollute our air ! I know in TEXAS, they don't care much for the air, because I've lived there for 8 years......price is more important in Texas, not in California, because we have NO choice !
</font>
I am not sure that I have seen LOWER than 93 in California. WE don't want to pollute our air ! I know in TEXAS, they don't care much for the air, because I've lived there for 8 years......price is more important in Texas, not in California, because we have NO choice !
</font>
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- Kvit -
2001 CL-P Blue Sub 6
*Polarg BlHybrid M-6 Road lamps
*Polarg BlHybrid M-14 Turning Signal/M-4 Side Markers next
http://albums.photopoint.com/j/Album...725&a=10358832
01-05-2001, 10:36 PM
#16
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I use mobil 92 octane. Is it possible that another Mobil station could have a higher octane, because the one local to me does not.
-smak-
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2001 CL Silver Type S w/ nav, muds, locks & spoiler.
-smak-
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2001 CL Silver Type S w/ nav, muds, locks & spoiler.
01-05-2001, 10:54 PM
#17
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Here in New Joisey, we have an avergae of 93 octane and Sunoco has 94 octane for $1.62 a gallon. Gulf 93 is $1.55. But here's a dumb question..... aren't the ratings on the pump and the ratings in the owner's manual dervied from different standards? I know it used to be but not sure now. 
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01 CL-S NightHawk Black/Ebony Bowling Ball Interior
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01 CL-S NightHawk Black/Ebony Bowling Ball Interior
01-06-2001, 12:10 AM
#18
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You guys are lucky! I put in premium 91 and I pay around $1.95!! I stay in the SF-Bay area, and a while back, I remember having paid as much as [shudder} $2.25!! I get around 20mpg.
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CL/S/Nav - Red/Ebony/Spoiler
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CL/S/Nav - Red/Ebony/Spoiler
01-06-2001, 12:45 AM
#19
Bagged hybrid
CLDemon - I feel your pain man. Which part of Sunnyvale are you from? I'm near Ranch 99 and Fantasia. Gas is very expensive here and we only get 91 octane in Cali...it sux!
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2001 Acura CL Type-S Satin Silver/Ebony
Debadged, PIAA Roadlamps, M-11 Turn signals, Comptech Headers, Comptech Springs, custom intake
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2001 Acura CL Type-S Satin Silver/Ebony
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01-06-2001, 01:48 AM
#20
Burning Brakes
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<font face="Verdana, Arial" size="2">Originally posted by gto2050:
Here in New Joisey, we have an avergae of 93 octane and Sunoco has 94 octane for $1.62 a gallon. Gulf 93 is $1.55. But here's a dumb question..... aren't the ratings on the pump and the ratings in the owner's manual dervied from different standards? I know it used to be but not sure now.
</font>
Here in New Joisey, we have an avergae of 93 octane and Sunoco has 94 octane for $1.62 a gallon. Gulf 93 is $1.55. But here's a dumb question..... aren't the ratings on the pump and the ratings in the owner's manual dervied from different standards? I know it used to be but not sure now.
</font>
I'm confused. What your saying about octane ratings and different standards between the pump and the owners manual, I'm not familar with that? Care to elaborate or point me somewhere?
Btw for the extra $2-$3 a week burned by using the best available grade, instead of using a lower but still acceptable grade, IMHO ain't worth the sweat for a $30k car . Might even get better milage which makes it an even trade anyway.
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01 CL Type-S, White/Black/Navi/Comptech Springs+Sways/Burl Shifter/Guards
01-06-2001, 03:24 AM
#21
I'm out of HELL!!!!
I've been using Amoco 93 since I got the car. Never a knock, never a problem.
Back a few months ago I was paying $1.89/gallon. It's calmed down to $1.71/gallon.
I always fill up when I have to travel to NJ for work. They have much cheaper gas (thanks to less state tax).
-RM
Long Island, NY
robonli@hotmail.com
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2001 Silver Acura CL Type S
1997 Ford Probe (POST)
Back a few months ago I was paying $1.89/gallon. It's calmed down to $1.71/gallon.
I always fill up when I have to travel to NJ for work. They have much cheaper gas (thanks to less state tax).
-RM
Long Island, NY
robonli@hotmail.com
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2001 Silver Acura CL Type S
1997 Ford Probe (POST)
01-06-2001, 03:59 AM
#22
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I use Chevron 92 which is around $2.08 - $2.11 a gallon (gas is VERY expensive in the bay area). Theres a 76 on the other side of San Jose that has 100 octane, maybe i'll put it in the CL the weekend.
01-06-2001, 10:07 AM
#23
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<font face="Verdana, Arial" size="2">Originally posted by gto2050:
aren't the ratings on the pump and the ratings in the owner's manual dervied from different standards? I know it used to be but not sure now.
</font>
aren't the ratings on the pump and the ratings in the owner's manual dervied from different standards? I know it used to be but not sure now.
</font>
ASnyway, US Octane ratings are based on the following formula:
( RON + MON ) / 2
Where RON and MON are different ratings for Octane. So no, the rating is the same everywhere but the engines may like certain mixtures better. Such as more RON than MON (forgot the actual definitions of both) or vise versa.
But remember, you don't hear 90% of the knock. When you hera it damage is already occuring. Albeit, it may not be measureable but over time it will be.
Always use the recommened grade and you should be fine. But avoid suspect stations that you think might fill the 93 tanks with 89...
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02-09-2013, 01:43 PM
#26
I Wanna Beer
I've always used 91/93. I believe Acura says that while you can get away with using other than premium, the ECU will adjust timing which results in less HP output and less mileage.
Really it's only another $1-2 per tank to go premium over normal unleaded. Spend the extra little bit and give the car what it's suppose to get.
Really it's only another $1-2 per tank to go premium over normal unleaded. Spend the extra little bit and give the car what it's suppose to get.
02-11-2013, 11:35 AM
#28
Senior Moderator
02-12-2013, 03:12 AM
#29
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$6.68 a gallon for premium north of the border and that adds up to an additional 7 bucks a tank (full tank, mind you) over regular but I'm worth it and my car is too...
02-12-2013, 09:41 AM
#30
I Wanna Beer
Ouch. Generally here midgrade is about 10¢ more per gallon than standard unleaded and premium is 10¢ more than that. So 20¢ more a gallon than unleaded which with a 15 gallon tank is only $3 more per tank. I'm also lucky since Minnesota has close to the lowest gas prices in the US.
02-12-2013, 09:42 AM
#31
Maybe unlike others, he's really really really good with the "search" function.
I always use 87 because my car is old and ultimately this is still a honda engine and it will run either way. Where I notice the lower octane making a difference is if you are buying from Circle K, Arco, or Chevron/QT. I know many think it's a hype but Chevron and QT really do offer a better performing fuel that I can personally "feel" at the pedal when I'm driving. Once I used Arco gas and my car was soooo sluggish and bogged down.
I always use 87 because my car is old and ultimately this is still a honda engine and it will run either way. Where I notice the lower octane making a difference is if you are buying from Circle K, Arco, or Chevron/QT. I know many think it's a hype but Chevron and QT really do offer a better performing fuel that I can personally "feel" at the pedal when I'm driving. Once I used Arco gas and my car was soooo sluggish and bogged down.
02-12-2013, 01:44 PM
#32
Senior Moderator
Maybe unlike others, he's really really really good with the "search" function.
I always use 87 because my car is old and ultimately this is still a honda engine and it will run either way. Where I notice the lower octane making a difference is if you are buying from Circle K, Arco, or Chevron/QT. I know many think it's a hype but Chevron and QT really do offer a better performing fuel that I can personally "feel" at the pedal when I'm driving. Once I used Arco gas and my car was soooo sluggish and bogged down.
I always use 87 because my car is old and ultimately this is still a honda engine and it will run either way. Where I notice the lower octane making a difference is if you are buying from Circle K, Arco, or Chevron/QT. I know many think it's a hype but Chevron and QT really do offer a better performing fuel that I can personally "feel" at the pedal when I'm driving. Once I used Arco gas and my car was soooo sluggish and bogged down.
02-12-2013, 02:58 PM
#33
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02-13-2013, 07:37 AM
#34
Don't see why it really matters. It's a topic of that still holds interest in discussing not to mention how amusing it is to see gas prices rising (inflating) from 12 years ago.
For the record, post j32a2 engines were designed to be ran on 91 and up octane fuel for a reason. They produce a respectable amount of power for their time and not to mention their knock sensor systems weren't exactly ideal for detecting engine detonation and that means running anything below the recommended octane level could have long term affects...possibly with no ill effects at all other than lowered performance and power. Detonation over time will lower life expectancy on any motor.
For the record, post j32a2 engines were designed to be ran on 91 and up octane fuel for a reason. They produce a respectable amount of power for their time and not to mention their knock sensor systems weren't exactly ideal for detecting engine detonation and that means running anything below the recommended octane level could have long term affects...possibly with no ill effects at all other than lowered performance and power. Detonation over time will lower life expectancy on any motor.
02-28-2013, 01:22 PM
#35
Food for thought:
It all depends on what elevation you're at (if you have a N/A engine). If you're at a higher elevation (I'm in Calgary, AB Canada), your high compression engine will perform better running 89 than 91... since the atmospheric pressure is lower, the engine will actually like a fuel that is slightly more prone to detonation.
A local guy here has done studies with a few naturally aspirated cars that he's bought brand new over the last few years, and every one of them runs better and produces more power on 89 when 91 is actually the recommended grade (he's dyno tested them for proof).
It all depends on what elevation you're at (if you have a N/A engine). If you're at a higher elevation (I'm in Calgary, AB Canada), your high compression engine will perform better running 89 than 91... since the atmospheric pressure is lower, the engine will actually like a fuel that is slightly more prone to detonation.
A local guy here has done studies with a few naturally aspirated cars that he's bought brand new over the last few years, and every one of them runs better and produces more power on 89 when 91 is actually the recommended grade (he's dyno tested them for proof).
02-28-2013, 01:29 PM
#37
You're right, they correct the timing so the engine runs well with what its given.
But if you give it 89 at our elevation, the result after ECU correction is better than the result after ECU correction for 91... so the engine can adjust timing for either one, but it will produce more power with correct timing while running 89. Does that make sense?
But if you give it 89 at our elevation, the result after ECU correction is better than the result after ECU correction for 91... so the engine can adjust timing for either one, but it will produce more power with correct timing while running 89. Does that make sense?
02-28-2013, 09:11 PM
#38
Wow. Getting pretty deep. I run only 91 octane premium in my '03 CL-S. Have never tried mid-grade. Only drive this car on weekends when its nice, so fuel cost really not a concern. My wife runs 89 octane mid grade in her daily driver '08 TL Base. Have not noticed any issues and it seems to do just fine. Hell, the only reason I have the '03 is becuase the '08 is the best car we have ever owned.
03-23-2013, 12:42 AM
#40
^89 octane does not produce more power than 91 because of the octane level itself.
If that test is accurate, it is more likely to be caused by the ingredients of 89 versus the ingredients of 91. Since ethanol has an octane of ~100, most 91 octane gas simply have a higher concentration of ethanol than gasoline.
The ethanol has less energy per volume compared to gasoline, so the 89 overall has more energy per volume. This is not because of the octane level, but rather because of the cheaper route of making 91 via more ethanol.
If that test is accurate, it is more likely to be caused by the ingredients of 89 versus the ingredients of 91. Since ethanol has an octane of ~100, most 91 octane gas simply have a higher concentration of ethanol than gasoline.
The ethanol has less energy per volume compared to gasoline, so the 89 overall has more energy per volume. This is not because of the octane level, but rather because of the cheaper route of making 91 via more ethanol.