Yuille36

With fuel prices for premium escalating everyday, you might be tempted to use a midgrade fuel or God forbid regular unleaded. But be warned... Even with the high fuel prices only use premium fuels. The vehicle was designed and built for performance so anything less is not recommended. The lower the octane the more detonation will occur in the combustion chamber causing quenches which is combustion before the piston reaches top dead center, this will retard ignition causing low power output and with time excessive carbon build up on the piston tops and cylinder head which can lead to rough idle, long cranking time during start up, knocking noise in engine on light throttle acceleration and sometimes knocking when engine is cold. Some cases can cause oil consumption due to sticking piston rings from carbon. Carbon build up is not covered under warranty.
Some people say gas is gas..... If that is true then why do Motorsports teams use special racing fuel? And why do gas station have different grades? Wouldn't it be in the manufactures best interest to tell customers they can use regular gas?
I watch people constantly use regular fuel in vehicles that require premium every time I'm at the pumps... Very sad.

Evolved8

Although prices are high, If your debating trying to save by using mid grade thats a BAD idea. And it will only save you $5.00. NOT worth a blown motor, ETC. Don't skip out on the basic stuff. Your driving an AMG

skratch77

nothing wrong with using 91 oct if you have a stock car and if your tune is not on the agressive side.

People in cali only get 91oct

GT-ER

I've been tempted to drive my pickup to work instead of the amg. It gets better fuel economy although it's somewhat uncomfortable.

skratch77

Iv been driving my honda accord this winter,I dont care how much gas costs.Not driving the amg for 3 months is worth the extra in gas when its back on the road.

Getting 30mpg is also a plus with the accord for when gas gets 4.50/gallon.

with my last tune before we leaned it out a little I got 113 miles on a full tank of gas with the beast.That would cost me over 300 a month just to get to work everyday.

saltydizzle

IMO. The higher 87 octane goes the more affordable 93 is. Say 87 is $3.75/gal and 93 is $4.00/gal....you are only paying 6% more for 93. If 87 was at $2.00/gal and 93 was $2.25/gal you would be paying 12% more for 93.

Yuille36

The news reports are predciting $4 by summer, can the news be any dimmer. I remember a few years ago, when regular was over $4, and premium was like $4.50.
My wallet took a big hit when I had to fill up the E63, but back then I drove my Mini Cooper S more than the E63. Well, I can't say that anymore, as both of my cars are AMGs. But eventually gas prices will taper off and settle back down, as the demand decreases, and the Middle East Crisis settles.

UK-C200

Joy - I'd love $4.50 premium. Most of the rest of the world is and has been paying just a bit more for a long time. I filled up yesterday at $8.52 a gallon. Enjoy the cheap gas stateside.

Quadcammer

there are so many things wrong and factually inaccurate in your post that i dont even know where to start

motorkas

Was just about to go there as I leave to Europe tomorrow. . .I've all but stopped doing the the conversion in my head of liters to gallons/ Euros to dollars. Don't get me wrong - anytime I get over 60.00 for a fill up, I get a little tweaked (I think it has more to do with the fact that gas taxes are SUPPOSED to pay for updating our infrastructure which I don't see) but it does always give me perspective about how bad gas prices could be (on a side note - traffic is just as bad but the roads are so much better). Either way, my daily is a camry hybrid and when the A/C's not on, I get close to 500 miles to a 14 gallon tank...

izzyz28

Compared to the rest of the costs associated with owning this car(car payment, insurance, maintenance, etc etc..), an extra $50 to $100 a month in gas isn't really even worth thinking about. People get all retarded about gas prices, and rather than suck it up they go and do something really stupid like buy ANOTHER more efficient car to drive and insure while the nice car/SUV sits collecting dust and depreciating.

Lycan

Good post....well you can actually run a few tanks of it though with no problem. I had this issue with my ZO6 living in an area that only sold 91 at the best. But given the choice stick with the Premium stuff.

Lycan

+1

Yuille36

I have to go put some gas in the tank myself. I never let any of my cars tanks get below a half tank. As a Marine you never let your Humvee run out of fuel. Well, that has stuck with me thru retirement. The bottom line, is that you have to pay to play...!

Alps

in the UK, the lower octaine fuel is 95 and the usual high octain (super) is 98-99, there is even a 101 octain fuel at selected BP pumps, but its double the price!

Yuille36

UK-C200,

Yes, in Europe and Australia your gas prices are double to what we're paying. So we shouldn't be complaining, but rejoicing at our prices.
Your jungle juice has higher octane compared to our kool aid. So in comparison your running racing fuel, and we're running watered down apple cider

Yuille36

First off, I was curious about this whole octane rating thing. So, I called my friend who is an AMG Master Tech. And this was our conversation roughly translated on the phone. You don't have to agree with me, your entitled to your own opinion. But if you have something factual to add then posted it.

novae500

ill be driving my 99 civic si again once it get it up running. Didnt drive it for 3 months since it cuts out on me when it get belows 30degrees. Too cheap to fix the alternator rather spend $$ on getting my benz modded:-). Driving the civic during the summer is the way to go for me.

Yuille36

I lived in Hawaii for 4 1/2 yrs, and we always had high gas prices. As you know Hawaii has no oil refineries, and fuel had to be imported. I would watch the news, and hear about gas prices on the mainland, and I simply said to myself "And there complaining, they need to come here".

Quadcammer

No problem. The M113 ML55 powerplant powering the E55 has a 9.0:1 compression ratio. It also has a clutched supercharger.

henceforth, when you are not heavily loading the motor, the engine will loaf along like any other 9.0cr motor. The Bosch motronic ecu uses both knock sensors and other sensors like the ECT, IAT, MAP sensor and others to determine timing maps.

now, lets say someone was taking a long trip on a highway where they did not intend to heavily load the motor.

By running 87 octane, the car would run just fine as the computer would continually adjust the timing curve based on whether or not it sees detonation. This part we agree on.

However, your argument that running 87 will cause carbon build up has no basis in fact. By retarding the timing to the limit of spark knock, you are still fully burning the fuel (to at least the commanded a/f anyways). Where is the carbon build up coming from in this instance?

My point is this:

You can run 87 all day long if you don't plan on getting on it. The car will run fine even if you DO get on it, but you will obviously be down on power, and quite frankly, relying on a knock sensor is a dangerous gamble on a $40,000 engine.

I wouldn't run regular or midgrade, but to say it will result in nearly instantaneous carbon build up is not supported by fact.

Yuille36

I never said instantaneous carbon build up, you just interpreted it as such.
Overtime yes, instantaneous no. Can we just agree to disagree and move on from here

JohnEnglish

Actually it's the same amount of octane, they just use a different rating system.

87 Octane in North America is the same as 92 Octane in Europe

94 Octane in North America is the same as 98 Octane in Europe

Yuille36

Thank you for educating us all, as I didn't know that

baldmike73

predicting $4 by summer - the Bay Area $4 was 2 weeks ago - gotta pay to play - still cheaper than EU

Yuille36

Well this afternoon, I had to put some gas in my E63, because I make it a point not to let it fall below a half tank. Anyway I was able to find premium for $3.69. The car took 11 gallons and I paid $41.00. If it was on empty, it would have cost me at least $85 to fill up, and this was in Stafford, VA.