91 vs. 87 Octane?
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91 vs. 87 Octane?
My 07' E350 says to use 91 octane. But with gas here in So. California near 4 bucks a gallon (almost a quarter more than regular - why?) can you switch to a lower grade without hurting the car. I put in a tank of 87 octance recently by mistake... Didn't notice much of a difference.
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From: Valley of the Sun, Arizona
2011 E550, 2013 GLK
For 25 cents a gallon, you will be relying on the knock sensors retarding the ignition enough to keep you from destroying your engine. Not only that but you will be sacrificing fuel economy, power and a better additive package by using lower octane fuel.
I suggest that you stick to 91 octane which is borderline as it is.
I suggest that you stick to 91 octane which is borderline as it is.
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From: Ft. Lauderdale Area, USA
2015 ML 350
Figuring 15,000 miles a year at 15 MPG (...and your average MPG will be better than that) and Premium gas costing you 25 cents a gallon more than Regular, you will be spending $ 250.00 more a year on gas. Your car will perform better, and using Regular gas will decrease your MPG due to the engine computer retarding the timing so you don't get damaging pre ignition, or pinging. Assuming the load on the car, and how agressively you drive the car you can severely damage your engine.
Assuming you keep the car for 4 years, the difference in the total cost of this car versus one that was designed to burn Regular, and perform at its best amounts to $1,000.00 . If the best deal you could have gotten for a car of this caliber would have cost you $1,000 more, would you have passed on it?
Think logically. If the car would have cost a thousand dollars more, and the Dealer said they'd let you pay off the $ 1,000 over 4 years, however you wanted, as long as it was paid for in 4 years, that would have been a pretty good deal.
Thats what it is...
Assuming you keep the car for 4 years, the difference in the total cost of this car versus one that was designed to burn Regular, and perform at its best amounts to $1,000.00 . If the best deal you could have gotten for a car of this caliber would have cost you $1,000 more, would you have passed on it?
Think logically. If the car would have cost a thousand dollars more, and the Dealer said they'd let you pay off the $ 1,000 over 4 years, however you wanted, as long as it was paid for in 4 years, that would have been a pretty good deal.
Thats what it is...
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From: Maryland
Eurocharged 2004 E500, Eurocharged ECU/TCU 2005 SL600, 2010 Caddy SwaggerWagon
Figuring 15,000 miles a year at 15 MPG (...and your average MPG will be better than that) and Premium gas costing you 25 cents a gallon more than Regular, you will be spending $ 250.00 more a year on gas. Your car will perform better, and using Regular gas will decrease your MPG due to the engine computer retarding the timing so you don't get damaging pre ignition, or pinging. Assuming the load on the car, and how agressively you drive the car you can severely damage your engine.
Assuming you keep the car for 4 years, the difference in the total cost of this car versus one that was designed to burn Regular, and perform at its best amounts to $1,000.00 . If the best deal you could have gotten for a car of this caliber would have cost you $1,000 more, would you have passed on it?
Think logically. If the car would have cost a thousand dollars more, and the Dealer said they'd let you pay off the $ 1,000 over 4 years, however you wanted, as long as it was paid for in 4 years, that would have been a pretty good deal.
Thats what it is...
Assuming you keep the car for 4 years, the difference in the total cost of this car versus one that was designed to burn Regular, and perform at its best amounts to $1,000.00 . If the best deal you could have gotten for a car of this caliber would have cost you $1,000 more, would you have passed on it?
Think logically. If the car would have cost a thousand dollars more, and the Dealer said they'd let you pay off the $ 1,000 over 4 years, however you wanted, as long as it was paid for in 4 years, that would have been a pretty good deal.
Thats what it is...
Barry,
You always make my brain hurt. I hate smart people.
I look at it a more rudamentary fashion. If I fill either one of my cars up with super when they're completely empty, it's roughly 60 bucks. If I fill the same car up with regular, it's roughly 55-57 bucks, maybe, with a difference of about .15 per gallon. For a couple dollars a tank, I'll take the performance, fuel economy and peice of mind.
Last edited by Benz-O-Rama; May 16, 2007 at 10:53 PM.
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From: Palm Beach Gardens, Fl
‘08 E-350 Sport, C6 Vette & Harley Davidson
Ok .. flame away!
At 76, I've used regular all my life and don’t plan to change now! And - as you
might suspect - I go long on oil changes.
After millions (I assume) of miles I have never had an engine problem related
(even remotely) to excessive wear or detonation.
I used regular in my 06 DTS and I use regular in my current - and earlier - C6.
I no longer race, so I can’t tell the difference .. although I know that if “maxed
out” there would be some difference.
MANY years ago back in Ohio, when I was very active in tractor pulls, indeed I
DID use the maximun hot fuel available! But my tractor pulls have passed. So,
if my savings is one extra hamburg a month at McDonalds, that’s a good thing!
jimm
==========
On Order: 08 E350 Sport, P2, Black/black,
Parktronic, Voice, Bluetooth, Burl Walnut,
Split rear seat, Rear mud flaps
At 76, I've used regular all my life and don’t plan to change now! And - as you
might suspect - I go long on oil changes.
After millions (I assume) of miles I have never had an engine problem related
(even remotely) to excessive wear or detonation.
I used regular in my 06 DTS and I use regular in my current - and earlier - C6.
I no longer race, so I can’t tell the difference .. although I know that if “maxed
out” there would be some difference.
MANY years ago back in Ohio, when I was very active in tractor pulls, indeed I
DID use the maximun hot fuel available! But my tractor pulls have passed. So,
if my savings is one extra hamburg a month at McDonalds, that’s a good thing!
jimm
==========
On Order: 08 E350 Sport, P2, Black/black,
Parktronic, Voice, Bluetooth, Burl Walnut,
Split rear seat, Rear mud flaps
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From: Ft. Lauderdale Area, USA
2015 ML 350
Bear in mind that these cars were designed in Germany to run on higher octane fuel than is available in most places in the USA, so they are already factory 'detuned" to accept whatever octane we have here. As it says in the manual, your Caddy was designed here, and was designed to run on Regular gas, but it will perform better if you used Premium. But its your car. No flaming. If its good enough for you... Rock On!
Personally I can't see why someone would want a "Performance Sport Sedan" and then intentionally hobble it. There will be a trade off in performance.
Personally I can't see why someone would want a "Performance Sport Sedan" and then intentionally hobble it. There will be a trade off in performance.
Last edited by Barry45RPM; May 17, 2007 at 10:23 AM.
Super Member
Joined: Sep 2002
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From: New Jersey, USA
W211 & Q7
For 25 cents a gallon, you will be relying on the knock sensors retarding the ignition enough to keep you from destroying your engine. Not only that but you will be sacrificing fuel economy, power and a better additive package by using lower octane fuel.
I suggest that you stick to 91 octane which is borderline as it is.
I suggest that you stick to 91 octane which is borderline as it is.
http://forums.audiworld.com/q7/msgs/14620.phtml
Member
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From: Lawn Guyland,NY
'07 E350W4
Bear in mind that these cars were designed in Germany to run on higher octane fuel than is available in most places in the USA, so they are already factory 'detuned" to accept whatever octane we have here. As it says in the manual, your Caddy was designed here, and was designed to run on Regular gas, but it will perform better if you used Premium. But its your car. No flaming. If its good enough for you... Rock On!
Personally I can't see why someone would want a "Performance Sport Sedan" and then intentionally hobble it. There will be a trade off in performance.
Personally I can't see why someone would want a "Performance Sport Sedan" and then intentionally hobble it. There will be a trade off in performance.
Out of curiosity, what is the comparative octane of gas in Germany?
There's a station near me that sells, or used to anyway, 166 octane fuel at a select pump. I remember it was 2-3X the price of regular gas
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From: Valley of the Sun, Arizona
2011 E550, 2013 GLK
Refuel using only unleaded premium grade petrol with a minimum octane number of 95 RON/85 MON conforming to European standard EN 228.
You could otherwise impair engine output or damage the engine.
You will find further information about petrol under “Technical data” in the index.
You will generally find information about the petrol grade on the filling pump. Otherwise, ask the filling station attendant.
If the recommended fuel is not available and only as a temporary measure, you may also use regular unleaded petrol, 91 RON/82.5 MON. This may reduce performance and increase petrol consumption. Avoid driving at full throttle.
In some countries, the available petrol quality may not be sufficient and could cause coking around the inlet valve. In these cases, and in consultation with a Mercedes-Benz Service Centre, the petrol may be mixed with the additive sold and recommended by Mercedes-Benz (part no. A000989254510). You must observe the notes and mixing ratios given on the container.
RON is roughly equal to PON (US) although not always. I don't think fuel in Germany is burdened with additives like ethanol.
There is a Super grade of gasoline in Germany that has a RON of 98.
Last edited by BudC; May 17, 2007 at 01:34 PM.
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From: Toronto
2006 E320 CDi, 2008 3/4 Ton Suburban, 2007 "rice rickshaw" Accord 5 speed
Penny wise Pound foolish
My 07' E350 says to use 91 octane. But with gas here in So. California near 4 bucks a gallon (almost a quarter more than regular - why?) can you switch to a lower grade without hurting the car. I put in a tank of 87 octance recently by mistake... Didn't notice much of a difference.
MBWorld Fanatic!
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From: Ft. Lauderdale Area, USA
2015 ML 350
The manual states that if you can't get Premium, to put in what you need with the highest octane you can find, then switch back to Premium at the soonest interval. (To average the octane.)
We can debate this for ever... so seeing all of the above, put in whatever you want into your car, just like I'm sure is done in the loaner cars.
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Gasoline in Germany was always sold in three grades with RON 91, 95, 98. Over the past couple of years, 91 is being phased out or offered at fewer pumps because of diminshing demand (most cars require at least 95, some even 98 min like MB V12 and AMG). Also, Shell and Aral (BP) have eliminated 98 in favor of 100 octane. In summary, when buying gasoline, you will always see 95, and either 98 or 100, maybe 91.
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My 07' E350 says to use 91 octane. But with gas here in So. California near 4 bucks a gallon (almost a quarter more than regular - why?) can you switch to a lower grade without hurting the car. I put in a tank of 87 octance recently by mistake... Didn't notice much of a difference.
Member
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From: Palm Beach County, Fl.
W163 ML500 w/Kleeman headers (gone but not forgotten); R63
I picked up my '02 ML500 used and put in only 93 octane for the first few months. With plenty of torque and stiff gearing (3.7) I wondered what would happend if I tried 87. I did and I can't tell the difference in mileage or power in everyday driving. Even when I towed about 4000#'s, I had no problems on regular (although I would use at least half a tank of 93 in hot weather).
BTW, I use 93 only in my turbo car and my M car, but the MB seems happy on either.
Regards,
Jerry
BTW, I use 93 only in my turbo car and my M car, but the MB seems happy on either.
Regards,
Jerry
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Joined: Sep 2005
Posts: 18,414
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From: West Michigan
2007 E63
I picked up my '02 ML500 used and put in only 93 octane for the first few months. With plenty of torque and stiff gearing (3.7) I wondered what would happend if I tried 87. I did and I can't tell the difference in mileage or power in everyday driving. Even when I towed about 4000#'s, I had no problems on regular (although I would use at least half a tank of 93 in hot weather).
BTW, I use 93 only in my turbo car and my M car, but the MB seems happy on either.
Regards,
Jerry
BTW, I use 93 only in my turbo car and my M car, but the MB seems happy on either.
Regards,
Jerry
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From: Ft. Lauderdale Area, USA
2015 ML 350
The Engine Computer retards the timing as much as necessary so as not to ping and do any harm to the engine. Retarded timing yields less power & worse MPG. Eventually the computer can't retard the timing any more & keep emission standards... thats when damage can occur.
Newbie
Joined: Apr 2007
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From: Honolulu, Hawaii
2003 E500
SO would octane additives help since we can only get a certain octane when actual we should be running something higher? Those octane additves any good? Not that cheap though, and I can't imagine adding a bottle every time you fill up.
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I use regular on my BMW even though it says Premium only. I have been doing that ohh about for the last 170,000 miles and never had a problem. Few times I switched to Premium for couple weeks at a time but I just can't feel the difference in performance or the fuel economy. My engine at 180K miles runs like new, not even burning a drop of oil. So regular gas for me.
I know for porsche 911 it makes about 11hp difference but even then it is almost impossible to detect via butt dyno. 911 engine is a high strung/compression engine so I doubt if MB looses that much power, may be 5hp.
I assume MB having the 2.6L engine which is almost same as my BMW, it will behave the same.
I know for porsche 911 it makes about 11hp difference but even then it is almost impossible to detect via butt dyno. 911 engine is a high strung/compression engine so I doubt if MB looses that much power, may be 5hp.
I assume MB having the 2.6L engine which is almost same as my BMW, it will behave the same.
Last edited by gokcer; Jun 12, 2007 at 06:28 PM.
