What octane gas to use in a bmw?

Premium fuel is only not worth the money in an engine that does not require
it.

If the engine requires it, it is worth every penny.





> wrote in message
...
> Anyone use higher than 87? The guy who sold me my 740IL said he never
used
> anything but 93, yet I see "experts" claiming that any of the premium
> gasolines are not worth the extra money....
>
>

> wrote in message
...
> Anyone use higher than 87? The guy who sold me my 740IL said he never
used
> anything but 93, yet I see "experts" claiming that any of the premium
> gasolines are not worth the extra money....
>
I use always the highest octane available (in US), because it still three
times cheaper than what I paid back at home (in Europe

Seriously, I drive for two weeks with a full tank of gas. If I save 20c per
gallon by using lower grade, that totals $6 dollars savings a month. What
difference does that make? Oh, free gallon of organic milk

BR:Z

> If the engine requires it, it is worth every penny.

:-D you should try feeling the difference between my celica turbo with
regular or optimax - worlds of difference. As you say, if the manufacturer
set the car up to run on premium it is going to underperform and cause
issues if you dont use it. My manufacturer ECU manual shows how if it
detects knock from non-premium gas it drops my turbo pressure, retards the
timing and increases the fueling slightly. Not the same as a NA car but
modern high compression engines run on similar principles.

J

Or $6/month compounded for $30-40 years?


"Zon" > wrote in message
...
> > wrote in message
> ...
>> Anyone use higher than 87? The guy who sold me my 740IL said he never
> used
>> anything but 93, yet I see "experts" claiming that any of the premium
>> gasolines are not worth the extra money....
>>
> I use always the highest octane available (in US), because it still three
> times cheaper than what I paid back at home (in Europe
>
> Seriously, I drive for two weeks with a full tank of gas. If I save 20c
> per
> gallon by using lower grade, that totals $6 dollars savings a month. What
> difference does that make? Oh, free gallon of organic milk
>
> BR:Z
>
>

That is not true. The detergent packages differ from one company to another,
and from one grade to another. When I used to work for an oil company, the
additive package we used for the premium gas cost $65/gal, for reg and plus
it was $9.50/ gal. And yes the state inspects the fuel loading and additive
injector equipment every 6 months.

To answer the question,...

Use the lowest grade of gasoline that allows the engine to operate without
knocking (detonation, pinging...). All cars built after 1995 are OBDII
controlled. They all have knock sensors, usually more than one. When the
engine is in closed loop operation, (not WOT), if knock (detonation) is
detected the ECU reduces the amount of ignition timing until the knock
stops. This will result in a dramatic reduction of the engines power.

My BMWs' engine was designed and rated to run on 95 RON gas. That about 90.5
(R+M)/2. (R+M)/2 is the pump rating, so think plus. The owners manual
states that the engine will run on reg (87) but performance will be better
with higher octane gas. The Conforti chip I have requires that I use premium
gas only. 93+


"Matt O'Toole" > wrote in message
...
> wrote:
>
>> > detergents, etc. But now all grades are the same except for octane,
>> > and paying
> for more octane than you need is a waste of money.
>
> Matt O.
>
>