[darkfact]

there usual are two types of gas in the gas stations here. Both of them unleaded. One of them is Premier and the other one is Super Premier I think.

all our lives we used the Super Premier for our cars. And everyone is still using it. whether a person is driving a Ferrari or a Mercedes… he’ll use the Super Premier.

But about a year ago a new gas was introduced. Its called Ultra Super Premier. They say its for high performance cars.
I’m not sure if car is considered one of them especially that most of the cars here are Ferraris, Austin Martins and carp like that

Anyways, I tried it on my car, C200K coupe, for a couple of weeks. There is a huge noticeable difference.
The car feels light, and by just putting my foot on the gas it goes fast (comparing to the normal gas).

After two weeks… now I switched back to the normal gas, and I really can’t drive it that way. I got used to it when it was with the ultra super gas. Take offs on turns is really annoying now.

I would continue to use the ultra super. But there is a major problem… the normal gas usually last with me for a week or a couple more days.
This ultra super gas lasts for three days only! though I go to the same places, take the same routs and drive in the same style!

Its really noticeable that I can’t go too far with this ultra super gas.

Is it possible to fix this problem by changing some setting through DAS or whatever they call it?

Thanks.

 

[Scheissmeisser]

You'll get the best fuel mileage

with the lowest octane that will run at load without detonation.Higher octane alone does not mean higher energy or more power.

 

[texnteg]

the engine will run cooler with a higher octane though, stick with what mercedes recomme...

the engine will run cooler with a higher octane though, stick with what mercedes recommends. there was an interesting article in the USA today this past wednesday on octane uses. mercedes said in regards to using a lower octane...that they don't think it will be a problem, but the computer will retard the power or timing to prevent detonation.

 

[Scheissmeisser]

Could you explain to us

why "the engine will run cooler with a higher octane"?.All I'm saying is that using higher octane fuel than the engine or the manufacturer requires is a waste of money.If the ECM has to compensate by retarding the ignition timing,the octane is too low.Useable,but still lower than what the engine was desined for.

 

[Drew]

I don't understand either...

why "the engine will run cooler with a higher octane"?.All I'm saying is that using higher octane fuel than the engine or the manufacturer requires is a waste of money.If the ECM has to compensate by retarding the ignition timing,the octane is too low.Useable,but still lower than what the engine was desined for.

Not only that but if the engine has to keep retarding the timing, that will result in poorer fuel economy, negating the lower price of regular fuel. Honestly I wonder some times how MB owners can afford the cars but stinge on the fuel. Perhaps since so many people lease them these days, they don't really care as they don't own the cars.