What Gas Do You Use
Thread Starter
Super Member
Joined: Nov 2001
Posts: 618
Likes: 0
From: Kansas City
2010 E550
What Gas Do You Use
My tech advisor told me something the other day that I had never heard. He asked what kind of gas I was using and I told him 91 octaine. He said to us 89 and to go to a station that has a high volume. He said that the car can take 89 and that it adjusts for it automatically. He also said that since a lot of people don't use 91 that it sits in the tanks longer and developes moisture which can be bad for your engine.
Of course maybe this does not apply to you folks in California that may go through gas a lot quicker than we do and the tanks never develope moisture because there is a high volume use of 91 octaine.
Anyone ever heard this or have any thoughts. I wondered if I used 89 if I might be losing HP and god knows I don't want to do that!
Of course maybe this does not apply to you folks in California that may go through gas a lot quicker than we do and the tanks never develope moisture because there is a high volume use of 91 octaine.
Anyone ever heard this or have any thoughts. I wondered if I used 89 if I might be losing HP and god knows I don't want to do that!
Almost a Member!
Joined: Jan 2002
Posts: 34
Likes: 0
From: Los Angeles
1995 C36 AMG
Having spent a solid amount of my high school years pumping gas in Oregon (cannot pump your own there) and eventually running just about everything at the station, I can say that the logic about seek stations with higher throughput is sound. Gas soaks up water when it just sits. As far as using 89 instead of 91, there are a couple of ways to look at it:
1) 89 octane almost always will test out to be near 90 if not over it.
2) 92 (what we had in Oregon) usually tests out to be under 92 and I would assume that 91 would test out to be 91 if not just a bit under.
3) for 90% of our customers that would ask for 92, we would fill the tank and then tell them to give 89 a shot next time as it would not make too much of a difference for them. Some of our customers then told us after trying 89 that the car seemed to run better (mostly lexus, infiniti and acura owners). The 10% that we would not recommend using 89 to were Mercedes, BMW and other high compression cars.
4) Your car will "adjust" to using 89, by retarding the timing if it pings (and it most likely will). This will reduce the available amout of power and mileage.
Long story short: 89 is great for most cars. For your's though, stick will 91 or higher and a good, high volume station.
~dnm
1) 89 octane almost always will test out to be near 90 if not over it.
2) 92 (what we had in Oregon) usually tests out to be under 92 and I would assume that 91 would test out to be 91 if not just a bit under.
3) for 90% of our customers that would ask for 92, we would fill the tank and then tell them to give 89 a shot next time as it would not make too much of a difference for them. Some of our customers then told us after trying 89 that the car seemed to run better (mostly lexus, infiniti and acura owners). The 10% that we would not recommend using 89 to were Mercedes, BMW and other high compression cars.
4) Your car will "adjust" to using 89, by retarding the timing if it pings (and it most likely will). This will reduce the available amout of power and mileage.
Long story short: 89 is great for most cars. For your's though, stick will 91 or higher and a good, high volume station.
~dnm
Member
Joined: Jan 2003
Posts: 217
Likes: 0
From: Gulf Shores, AL
E500 Sport
What about brand of Gas?
Any thoughts on brands to advoid or look for?
I'm using BP 93 octane now. It's a very hige volume station. But, I also have access to Shell, Texaco, Amoco, Conoco, Exxon, etc. I've always been told to advoid Conoco. Never heard anything pro or con on BP, Shell, Texaco or Exxon. I also avoid the "No Name" stuff.
Regarding MB and high octane, I'm told you'll also get better mileage on high Octane wht MB. I've only ever used 93, so can't comment.
Thoughts anyone?
Mark
I'm using BP 93 octane now. It's a very hige volume station. But, I also have access to Shell, Texaco, Amoco, Conoco, Exxon, etc. I've always been told to advoid Conoco. Never heard anything pro or con on BP, Shell, Texaco or Exxon. I also avoid the "No Name" stuff.
Regarding MB and high octane, I'm told you'll also get better mileage on high Octane wht MB. I've only ever used 93, so can't comment.
Thoughts anyone?
Mark
Newbie
Joined: Apr 2003
Posts: 5
Likes: 0
What Gas Do You Use
My agent told me to use 89 octane also. The Chicken that I am, I used 93 Amaco/Shell. How can you tell who using what? The pumps allow you to choose between three different gases at a stand.
By the By, I am a newbie, got my pewter/charcoal E320 in Oct. I enjoy the car. Love the christmas tree effect, Interior lights, at night. Cheers.
MBWorld Fanatic!
Joined: Feb 2002
Posts: 6,061
Likes: 326
From: 2000 ft over the FL coast in a B-17
Various
Use what MBZ tells you to, beleive me they want our cars to run as well as possible and have the least amount of repairs, if the car ran better or had fewer maintenence issues on regular grade they would say to use it in the manual, but they are requiring a minimum of 91 for a reason.
I use either Mobil,Shell or Chevron
I use either Mobil,Shell or Chevron
Trending Topics
MBWorld Fanatic!
Joined: Oct 2002
Posts: 3,690
Likes: 2
From: Washington State
E-500
Re: What Gas Do You Use
Originally posted by MissyBenz
My agent told me to use 89 octane also. The Chicken that I am, I used 93 Amaco/Shell. How can you tell who using what? The pumps allow you to choose between three different gases at a stand.
By the By, I am a newbie, got my pewter/charcoal E320 in Oct. I enjoy the car. Love the christmas tree effect, Interior lights, at night. Cheers.
My agent told me to use 89 octane also. The Chicken that I am, I used 93 Amaco/Shell. How can you tell who using what? The pumps allow you to choose between three different gases at a stand.
By the By, I am a newbie, got my pewter/charcoal E320 in Oct. I enjoy the car. Love the christmas tree effect, Interior lights, at night. Cheers.
I would stick with the higher octane. MB would have no reason to advise the higher rating unless they felt it was needed. I just completed an 8200 mile road trip and did have to use the 89 octane a few times as it was all that was available. I was driving 400 to 500 miles many days so it did not stay in the tank long enough to make any difference. I did average about 23 mpg over the entire 8200 miles...city and highway...mostly highway at 80 - 85 mph. I am happy with the mileage under the circumstances.
Ed
MB World Stories
The Best of Mercedes & AMG
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
Newbie
Joined: Apr 2003
Posts: 5
Likes: 0
Re: Re: What Gas Do You Use
Originally posted by etenn
Welcome to the board......
I would stick with the higher octane. MB would have no reason to advise the higher rating unless they felt it was needed. I just completed an 8200 mile road trip and did have to use the 89 octane a few times as it was all that was available. I was driving 400 to 500 miles many days so it did not stay in the tank long enough to make any difference. I did average about 23 mpg over the entire 8200 miles...city and highway...mostly highway at 80 - 85 mph. I am happy with the mileage under the circumstances.
Ed
Welcome to the board......
I would stick with the higher octane. MB would have no reason to advise the higher rating unless they felt it was needed. I just completed an 8200 mile road trip and did have to use the 89 octane a few times as it was all that was available. I was driving 400 to 500 miles many days so it did not stay in the tank long enough to make any difference. I did average about 23 mpg over the entire 8200 miles...city and highway...mostly highway at 80 - 85 mph. I am happy with the mileage under the circumstances.
Ed
Thanks, etenn
Almost a Member!
Joined: Dec 2002
Posts: 65
Likes: 0
From: Melbourne, Australia
Hi all
I am sitting over here downunder in amazement, that you guys use 91 octane fuel over yonder ...
!!
The basic unleaded fuel in Australia is 91 octane, although MB's recommended fuel for Australian-spec'ed is 95 octane. Most European cars here run on 95+ octane, although will operate quite ok (albeit with reduced performance - so they say) with 91 octane. I only use 98 octane fuel, if I can help it!!
In Australia, there are two types of petrol - one is 'normal' unleaded - 91 octane, and the other is 'premium' unleaded - 95 to 98 octane, depending on brand. Most petrol stations stock 95 octane 'premium' unleaded, but Shell has Optimax (which is 98), BP has Ultimate (which is 98) and Mobil has 8000 (which is also 98)! Premium unleaded costs between 4 cents to 9 cents (Australian currency) more per litre than the 'normal' unleaded.
I am sitting over here downunder in amazement, that you guys use 91 octane fuel over yonder ...
!!The basic unleaded fuel in Australia is 91 octane, although MB's recommended fuel for Australian-spec'ed is 95 octane. Most European cars here run on 95+ octane, although will operate quite ok (albeit with reduced performance - so they say) with 91 octane. I only use 98 octane fuel, if I can help it!!
In Australia, there are two types of petrol - one is 'normal' unleaded - 91 octane, and the other is 'premium' unleaded - 95 to 98 octane, depending on brand. Most petrol stations stock 95 octane 'premium' unleaded, but Shell has Optimax (which is 98), BP has Ultimate (which is 98) and Mobil has 8000 (which is also 98)! Premium unleaded costs between 4 cents to 9 cents (Australian currency) more per litre than the 'normal' unleaded.
MBWorld Fanatic!
Joined: Apr 2002
Posts: 1,256
Likes: 0
From: Melbourne, Australia
E55, F550, S600 Ducati 999
craigng
The US uses different octane ratings to the rest of the world. In Australia we use the euro standards which are known as MON, the US uses PON.
98 MON =93 PON
95 MON =91 PON
The US uses different octane ratings to the rest of the world. In Australia we use the euro standards which are known as MON, the US uses PON.
98 MON =93 PON
95 MON =91 PON
MBWorld Fanatic!
Joined: Oct 2002
Posts: 3,690
Likes: 2
From: Washington State
E-500
Originally posted by stephens
craigng
The US uses different octane ratings to the rest of the world. In Australia we use the euro standards which are known as MON, the US uses PON.
98 MON =93 PON
95 MON =91 PON
craigng
The US uses different octane ratings to the rest of the world. In Australia we use the euro standards which are known as MON, the US uses PON.
98 MON =93 PON
95 MON =91 PON
Ed
Senior Member
Joined: Nov 2002
Posts: 454
Likes: 0
From: NC
'03 Mercedes E320
from a Medford Oil site: "OCTANE is rated in Research Octane Numbers (RON), Motor Octane Numbers (MON), and Pump Octane Numbers (R+M/2). Pump Octane numbers are what you see on the yellow decal on the pumps at the gas stations and represents an average of the two."
In the US we see the Pump Octane
In the US we see the Pump Octane
Thread Starter
Super Member
Joined: Nov 2001
Posts: 618
Likes: 0
From: Kansas City
2010 E550
This may be an elementary question but one that I don't know the answer to. What is the effect on performance of a higher octaine gas and what is the explanation for any difference?
Senior Member
Joined: Nov 2002
Posts: 454
Likes: 0
From: NC
'03 Mercedes E320
Not sure how much you want to know. Here's a thumbnail:
"The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more. "
<snip from "howstuffworks.com">
Your car will retard the timing (ignition) with lower octane fuels in order to stop ping, and when it retards, you lose performance. Thus, the higher the octane, the car avoids the ping and avoids retarding the timing, and you get optimum performance--i.e., closer to the stated horsepower.
"The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more. "
<snip from "howstuffworks.com">
Your car will retard the timing (ignition) with lower octane fuels in order to stop ping, and when it retards, you lose performance. Thus, the higher the octane, the car avoids the ping and avoids retarding the timing, and you get optimum performance--i.e., closer to the stated horsepower.
Senior Member
Joined: Nov 2002
Posts: 454
Likes: 0
From: NC
'03 Mercedes E320
Both the 500 and 320 are 10.0:1 compression--that's about the upper end for most street cars, limited by typical premium gas octane. An older design engine might be 8 or 8.5, more recent designs are in between but still recommend regular. Many now adjust to pinging, so you might see improved performance by stepping up to mid-grade or premium although the car is designed for regular.
