From Newsgroup: rec.autos.tech

On Tue, 20 May 2025 16:58:16 -0500, chrisv wrote :

CrudeSausage wrote:

For example, using 91 fuel in a regular engine is likely to damage
it in the long run,

No, I've never heard that. It's only a waste of money to use Premium
when it's not needed.

I agree with chrisv in that premium gasoline isn't better than regular any
more than penicillin is better than tetracycline. They're just different.

The only difference between a fuel rated at, oh, say, 125 octane and
another fuel rated at, oh, say, 100 octane, is the tendency to knock under
high heat and pressure.

Notice I'm choosing ratings above 100 because a lot of incredibly stupid peopple think the number is the percentage of "octane" in the fuel.

much in the same way that using 87 fuel in a 91 engine would.

Entirely different, as using insufficient octane can result in
predetonation (knock).

While I agree with chrisv, it is my understanding, which motorcheads may be able to better expound upon, that the point just microseconds prior to
knocking is the most efficient point in the ICE-engine combustion process.

You actually *want* to keep the engine just under the knock limit!

As far as I know, all modern engines have knock sensors which, if they
sense knocking, will slightly retard the timing back below the limit.

This is the most efficient way to run an engine at the highest thermal efficiency with the optimal spark advance.

Overall it means, in a sense, that premium is worse than regular, but my
point is not that but that most people don't understand any of this.

Most people only know what the marketing people told them.
All of which is wrong.

Bones become brittle from consumption of cow milk,

I recall asking you, some time back, to support that claim, and you
couldn't. Some quick google research (and common sense) says that
it's good for our bones.

I took Nutrition at Harvard in the seventies, taught by Jean Mayer, so it
was a looooooooooooong time ago but I think there was a Swedish study of
super high consumption of milk which that claim may be based upon. As I
recall, some researchers proposed this might be related to the sugar D-galactose in milk, which has been linked to oxidative stress and
inflammation in animal studies - but it was an abnormal amount of milk.

My opinion is that milk is not natural for adults, despite the claims from
the milk industry, particularly milk from another species where I would
tend to argue that humans can get all the calcium they need from various
plant sources (leafy greens, fortified plant milks, beans, etc.) and that
the calcium from some plant sources (like certain leafy greens) can even
have a higher absorption rate than calcium from cow's milk

Human milk is for human consumption, not cow milk.

Whatever it was "designed" for, it's still a good, healthy food.

My main point is that people believe only what MARKETING feeds them to
believe, but I don't disagree that ice cream is a great food, just as milk
is, as is cheese, and, especially, cheesecake!

My main beef is when the gob'ment puts stupid things like milk & bread
as a dietary requirement. They might as well have added alcohol too.

There are four food macronutrients, namely alcohol, carbs, fats and
proteins, where humans only need the latter two and not the former two.

My beef is why doesn't the government tell people the truth?
What's milk doing on their charts? They may as well have added vodka.
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On 2025-05-21 07:08, Marion wrote:

On Tue, 20 May 2025 16:58:16 -0500, chrisv wrote :

CrudeSausage wrote:

For example, using 91 fuel in a regular engine is likely to damage
it in the long run,

No, I've never heard that. It's only a waste of money to use Premium
when it's not needed.

I agree with chrisv in that premium gasoline isn't better than regular any more than penicillin is better than tetracycline. They're just different.

The only difference between a fuel rated at, oh, say, 125 octane and
another fuel rated at, oh, say, 100 octane, is the tendency to knock under high heat and pressure.

Notice that a gasoline with higher octane number allows the air-gasoline mixture to be compressed more, which makes the motor produce more power.

Possibly increasing the spark advance also increases the power yield, I
don't know for sure.

Notice I'm choosing ratings above 100 because a lot of incredibly stupid peopple think the number is the percentage of "octane" in the fuel.

Why do you have to insult people that simply do not know something?

...
--
Cheers,
Carlos E.R.
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On 5/21/2025 1:08 AM, Marion wrote:

On Tue, 20 May 2025 16:58:16 -0500, chrisv wrote :

CrudeSausage wrote:

For example, using 91 fuel in a regular engine is likely to damage
it in the long run,

No, I've never heard that. It's only a waste of money to use Premium
when it's not needed.

I agree with chrisv in that premium gasoline isn't better than regular any more than penicillin is better than tetracycline. They're just different.

Years ago, it was often marketed that the Premium also had better
additives. Today, Top Tier brands are the way to go.

In my Sonata with turbo, regular works fine, but just a half tank of 89
gives me better pedal feel. It is around town that I like it, on the
highway no difference. Seems to help with the turbo as it spools up.

I've played with the a few times, depending on when I fill, I alternate
to keep a slightly higher octane. I'd never bother with the 93. On my Genesis, non-turbo, straight 87 was good.
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On 21/5/2025 10:09 pm, Carlos E. R. wrote:

On 2025-05-21 07:08, Marion wrote:

On Tue, 20 May 2025 16:58:16 -0500, chrisv wrote :

CrudeSausage wrote:

For example, using 91 fuel in a regular engine is likely to damage
it in the long run,

No, I've never heard that.-a It's only a waste of money to use Premium
when it's not needed.

I agree with chrisv in that premium gasoline isn't better than regular
any
more than penicillin is better than tetracycline. They're just different.

The only difference between a fuel rated at, oh, say, 125 octane and
another fuel rated at, oh, say, 100 octane, is the tendency to knock
under
high heat and pressure.

Notice that a gasoline with higher octane number allows the air-gasoline mixture to be compressed more, which makes the motor produce more power.

Possibly increasing the spark advance also increases the power yield, I don't know for sure.

No. If the engine cannot utilise the increased knock resistance of the
higher octane fuel, the benefit will be wasted. In an engine that has
adaptive spark and knock sensors, it is possible that the ignition
timing can be advanced thereby altering the point of MBT - but don't
count on it. The point of MBT is pretty well defined on the original
octane fuel. You may also find the engine runs more smoothly on a higher octane fuel - but there will likely not be any advance on power.
Increase the compression ratio of the engine and then you will be
talking. Also, you can increase the *static* compression ratio or you
can increase the *dynamic* compression ratio. The dynamic (also known as effective) compression ratio directly relates to volumetric efficiency.

Notice I'm choosing ratings above 100 because a lot of incredibly stupid
peopple think the number is the percentage of "octane" in the fuel.

Why do you have to insult people that simply do not know something?

...

--
Xeno


Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On 21/5/2025 10:24 pm, Ed P wrote:

On 5/21/2025 1:08 AM, Marion wrote:

On Tue, 20 May 2025 16:58:16 -0500, chrisv wrote :

CrudeSausage wrote:

For example, using 91 fuel in a regular engine is likely to damage
it in the long run,

No, I've never heard that.-a It's only a waste of money to use Premium
when it's not needed.

I agree with chrisv in that premium gasoline isn't better than regular
any
more than penicillin is better than tetracycline. They're just different.

Years ago, it was often marketed that the Premium also had better
additives. Today, Top Tier brands are the way to go.

We have 3 levels of octane (RON) rating here 91, 95 and 98. 98, the
premium fuel, has a higher detergent rating so will keep injectors cleaner.

In my Sonata with turbo, regular works fine, but just a half tank of 89 gives me better pedal feel.-a It is around town that I like it, on the highway no difference. Seems to help with the turbo as it spools up.

I've played with the a few times, depending on when I fill, I alternate
to keep a slightly higher octane.-a I'd never bother with the 93.-a On my Genesis, non-turbo, straight 87 was good.

--
Xeno


Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On Wed, 21 May 2025 14:09:40 +0200, Carlos E. R. wrote :

Notice I'm choosing ratings above 100 because a lot of incredibly stupid
peopple think the number is the percentage of "octane" in the fuel.

Why do you have to insult people that simply do not know something?

My main point is that everything we think we know, is wrong.
My second point is that everything we think we know was fed to us.

We didn't formulate any ideas on our own.
Which is the problem I decry.

That's why I initially brought up gravity.
Everything anyone (save for a physicist) thinks they know, is wrong.

Even something as simple as gravity being a force - is wrong.
Likewise, orbiting astronauts are weightless in "zero gravity" - is wrong.

Higher-octane fuel being "better" because it costs more - is wrong.
Even bread/milk on a gob'ment dietary-requirement chart - is wrong.

Choosing ceramic over NAO or semi-metallic - is also wrong - but you have
to understand why it's wrong as there's nothing wrong with the materials.

People only know the marketing, where simply putting a spec of dust into a brake pad allows the marketing to claim good/better/best but it's wrong.

They don't understand anything about the product.
People only know what marketing has fed them to believe.

A classic case is Apple happens to have the absolute worst hotfix support
in the industry and yet most people believe that it's by far the best.

Who could possibly be that stupid?
I assess only one out of a million people can cut through the marketing.

It bothers me that marketing is mostly lies that stupid people believe.
It bothers me how much money these companies make out of stupid people.
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On Wed, 21 May 2025 08:24:57 -0400, Ed P wrote :

I agree with chrisv in that premium gasoline isn't better than regular any >> more than penicillin is better than tetracycline. They're just different.

Years ago, it was often marketed that the Premium also had better
additives. Today, Top Tier brands are the way to go.
In my Sonata with turbo, regular works fine, but just a half tank of 89 gives me better pedal feel. It is around town that I like it, on the highway no difference. Seems to help with the turbo as it spools up.
I've played with the a few times, depending on when I fill, I alternate
to keep a slightly higher octane. I'd never bother with the 93. On my Genesis, non-turbo, straight 87 was good.

I agree with Ed Pawlowski that there are highly marketed additives such as polyetheramines (some known by a specific brand name "Techron") which are nothing more than soap for gas whose patent expired long ago so now
everyone has them, even Costco (which is what Top Tier brands use).

This Techron garbage is classic marketing where what people think they know
is wrong, since, as Ed mentioned, it has nothing to do with the octane
rating and worse - it's not even something special anymore.

But people "think" that premium fuel cleans better - yet it's just another marketing l/xl/gxl bronze/silver/gold easy-for-people-to-choose numberline
to give people who are stupid a way to justify why they pay more for their gasoline than intelligent people pay.

As an aside, I once called up the parent company of "Chevron" to ask what Techron really meant, and they told me it means whatever they want it to
mean - which - after all - is the most honest answer I've ever gotten.

Trademarks don't have to mean anything.
Hence, they're used to mean whatever the company wants them to mean.

What they want it to mean is "better gas" but only stupid people think
that. And yet, Chevron makes a lot of money off of stupid people, don't
they.
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On Thu, 22 May 2025 00:00:00 +1000, Xeno wrote :

Years ago, it was often marketed that the Premium also had better
additives. Today, Top Tier brands are the way to go.

We have 3 levels of octane (RON) rating here 91, 95 and 98. 98, the
premium fuel, has a higher detergent rating so will keep injectors cleaner.

While the octane rating is calculated and measured (and then averaged) here
in the states, it's ultimately based on the knock propensity of two fuels.
a. 2,2,4-Trimethylpentane (which is assigned an octane rating of 100)
b. n-Heptane (which is assigned an octane rating of 0)

In the USA the octane rating displayed at the pump (the Anti-Knock Index or AKI) is the average of the RON and MON values, often written as (R+M)/2.

A. Research Octane Number
This test is conducted at lower engine speeds and temperatures,
simulating city driving or mild acceleration.
B. Motor Octane Number
This test is performed at higher engine speeds and temperatures,
simulating highway driving or more severe operating conditions.

Any association with polyetheramine detergents is merely a marketing ploy.
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On 2025-05-21 15:57, Xeno wrote:

On 21/5/2025 10:09 pm, Carlos E. R. wrote:

On 2025-05-21 07:08, Marion wrote:

On Tue, 20 May 2025 16:58:16 -0500, chrisv wrote :

CrudeSausage wrote:

For example, using 91 fuel in a regular engine is likely to damage
it in the long run,

No, I've never heard that.-a It's only a waste of money to use Premium >>>> when it's not needed.

I agree with chrisv in that premium gasoline isn't better than
regular any
more than penicillin is better than tetracycline. They're just
different.

The only difference between a fuel rated at, oh, say, 125 octane and
another fuel rated at, oh, say, 100 octane, is the tendency to knock
under
high heat and pressure.

Notice that a gasoline with higher octane number allows the air-
gasoline mixture to be compressed more, which makes the motor produce
more power.

Possibly increasing the spark advance also increases the power yield,
I don't know for sure.

No. If the engine cannot utilise the increased knock resistance of the higher octane fuel, the benefit will be wasted. In an engine that has adaptive spark and knock sensors,

which modern engines do, and I refer to those

it is possible that the ignition
timing can be advanced thereby altering the point of MBT - but don't
count on it. The point of MBT is pretty well defined on the original
octane fuel. You may also find the engine runs more smoothly on a higher octane fuel - but there will likely not be any advance on power.
Increase the compression ratio of the engine and then you will be
talking. Also, you can increase the *static* compression ratio or you
can increase the *dynamic* compression ratio. The dynamic (also known as effective) compression ratio directly relates to volumetric efficiency.

--
Cheers,
Carlos E.R.
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On 22/5/2025 2:24 am, Carlos E. R. wrote:

On 2025-05-21 15:57, Xeno wrote:

On 21/5/2025 10:09 pm, Carlos E. R. wrote:

On 2025-05-21 07:08, Marion wrote:

On Tue, 20 May 2025 16:58:16 -0500, chrisv wrote :

CrudeSausage wrote:

For example, using 91 fuel in a regular engine is likely to damage >>>>>> it in the long run,

No, I've never heard that.-a It's only a waste of money to use Premium >>>>> when it's not needed.

I agree with chrisv in that premium gasoline isn't better than
regular any
more than penicillin is better than tetracycline. They're just
different.

The only difference between a fuel rated at, oh, say, 125 octane and
another fuel rated at, oh, say, 100 octane, is the tendency to knock
under
high heat and pressure.

Notice that a gasoline with higher octane number allows the air-
gasoline mixture to be compressed more, which makes the motor produce
more power.

Possibly increasing the spark advance also increases the power yield,
I don't know for sure.

No. If the engine cannot utilise the increased knock resistance of the
higher octane fuel, the benefit will be wasted. In an engine that has
adaptive spark and knock sensors,

which modern engines do, and I refer to those

So was I. Pretty much everything has knock sensors these days and most
are adaptive. The ignition base timing map is calibrated to the rated
fuel octane, engine load and engine RPM. If you fill with a lower octane
fuel, the knock sensors will detect any knock and back off the timing.
If you fill with a higher octane fuel, the ECU has no way of knowing the
fuel is different so will continue to use the basic ignition timing map.
As an example, my car is rated for 91 RON fuel. If I fill with 95 RON,
the EMS has no way of detecting the change so will retain the same basic ignition timing map. On the other hand, if my car was rated for 95 and I filled with 91, the knock sensors would tell the ECU to back off the
timing. That would affect the adaptation and the EMS would create a new
timing map on the fly. That will mean the ignition timing will no longer
be optimal to give MBT. The greater problem is - the EMS will keep the ignition right on the hard edge of detonation and, long term, that won't
be good. Note, the knock sensors need to sense actual detonation before
they react. So, with the lower octane fuel present, there will always be
a tendency to knock. Note too, there are two ways to deal with knock.
The obvious one is to back off the ignition timing. The other is to
provide fuel enrichment. This occurs because the excess fuel cools the
flame front, preventing it from reaching peak temperatures.

it is possible that the ignition timing can be advanced thereby
altering the point of MBT - but don't count on it. The point of MBT is
pretty well defined on the original octane fuel. You may also find the
engine runs more smoothly on a higher octane fuel - but there will
likely not be any advance on power.
Increase the compression ratio of the engine and then you will be
talking. Also, you can increase the *static* compression ratio or you
can increase the *dynamic* compression ratio. The dynamic (also known
as effective) compression ratio directly relates to volumetric
efficiency.

--
Xeno


Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On Thu, 22 May 2025 12:49:45 +1000, Xeno wrote :

The greater problem is - the EMS will keep the
ignition right on the hard edge of detonation and, long term, that won't
be good.

Xeno knows more than I do about this but it's my understanding that the
best possible 'efficiency' (which I think he's calling maximum brake
torque) is when the engine timing is such that it's on the very verge of knocking.

Note that almost all the time, you're nowhere near the verge of knocking,
as it only happens, in normal sedate driving, at times of high load or acceleration or very high heat (which is an abnormal condition usually).

Note, the knock sensors need to sense actual detonation before
they react. So, with the lower octane fuel present, there will always be
a tendency to knock.

I've run many experiments on my bimmer which said it required premium,
where I never "heard" the knocking but more importantly - I never could
measure (with the crude methods available to me) any loss in MPG
calculations.

Of course, real MPG calculalations are usually done by before and after weighing a plastic bag of a known quantity of test fuel - so we'll NEVER be able to ascertain any difference in fuel economy by our crude methods.

Which is a key point....

1. You can pay 10 cents more per gallon every fillup of your life to
achieve a performance & economy of X... or...
2. You can pay 10 cents less per gallon every fillup of your life to
achieve essentially the same performanc & economy.

Point being, the word "always" in Xeno's statement, I think is wrong.

Hence, while I defer to Xeno's knowledge, it's my personal assessment that you'll ONLY knock under high heat/load situation which, depending on how
you drive, will almost never happen for most people who aren't racing.
--
I have abnormal wear of my front tires due to steep mountain windy roads causing "abuse" (aka camber scrub) as I never modified my caster to fix it. (Only Xeno will understand that statement.)
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On 2025-05-22 04:49, Xeno wrote:

On 22/5/2025 2:24 am, Carlos E. R. wrote:

On 2025-05-21 15:57, Xeno wrote:

On 21/5/2025 10:09 pm, Carlos E. R. wrote:

On 2025-05-21 07:08, Marion wrote:

On Tue, 20 May 2025 16:58:16 -0500, chrisv wrote :

CrudeSausage wrote:

For example, using 91 fuel in a regular engine is likely to damage >>>>>>> it in the long run,

No, I've never heard that.-a It's only a waste of money to use Premium >>>>>> when it's not needed.

I agree with chrisv in that premium gasoline isn't better than
regular any
more than penicillin is better than tetracycline. They're just
different.

The only difference between a fuel rated at, oh, say, 125 octane and >>>>> another fuel rated at, oh, say, 100 octane, is the tendency to
knock under
high heat and pressure.

Notice that a gasoline with higher octane number allows the air-
gasoline mixture to be compressed more, which makes the motor
produce more power.

Possibly increasing the spark advance also increases the power
yield, I don't know for sure.

No. If the engine cannot utilise the increased knock resistance of
the higher octane fuel, the benefit will be wasted. In an engine that
has adaptive spark and knock sensors,

which modern engines do, and I refer to those

So was I. Pretty much everything has knock sensors these days and most
are adaptive.-a The ignition base timing map is calibrated to the rated
fuel octane, engine load and engine RPM. If you fill with a lower octane fuel, the knock sensors will detect any knock and back off the timing.
If you fill with a higher octane fuel, the ECU has no way of knowing the fuel is different so will continue to use the basic ignition timing map.

You mean that the system is so stupid as not to recalibrate each time
you fill the tank?

Are all cars like this?
--
Cheers,
Carlos E.R.
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

Carlos E. R. wrote:

Xeno wrote:

So was I. Pretty much everything has knock sensors these days and most
are adaptive.a The ignition base timing map is calibrated to the rated
fuel octane, engine load and engine RPM. If you fill with a lower octane
fuel, the knock sensors will detect any knock and back off the timing.
If you fill with a higher octane fuel, the ECU has no way of knowing the
fuel is different so will continue to use the basic ignition timing map.

You mean that the system is so stupid as not to recalibrate each time
you fill the tank?

Are all cars like this?

No. All systems are constantly adaptive. They don't know or care
when the tank was filled.

--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

Marion <marion@facts.com> wrote:

Xeno knows more than I do about this but it's my understanding that the
best possible 'efficiency' (which I think he's calling maximum brake
torque) is when the engine timing is such that it's on the very verge of >knocking.

Maximum brake torque isn't the same as engine efficiency but they are correlated so we'll take that as close enough.

Note that almost all the time, you're nowhere near the verge of knocking,
as it only happens, in normal sedate driving, at times of high load or >acceleration or very high heat (which is an abnormal condition usually).

Yes, and that is why car engines are so inefficient and why hybrids have
such an efficiency win; the engine is designed for maximum power but
seldom operates at that regime.

Contrast this with an aircraft engine that is usually being operated at
close to full throttle all the time. (Admittedly the aircraft engine
allows the pilot or flight engineer to adjust the mixture control to
keep it always lean for efficiency but not too lean that it knocks.
Some allow fine timing adjustments too.)

Note, the knock sensors need to sense actual detonation before
they react. So, with the lower octane fuel present, there will always be
a tendency to knock.

I've run many experiments on my bimmer which said it required premium,
where I never "heard" the knocking but more importantly - I never could >measure (with the crude methods available to me) any loss in MPG >calculations.

Try that on a 2002 and you'll hear the knock and likely feel a pain in
the pocketbook for the valve job.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
--- Synchronet 3.21d-Linux NewsLink 1.2

From Newsgroup: rec.autos.tech

On Wed, 21 May 2025 18:14:18 -0500, Char Jackson wrote :

Note that all brake pads sold in the USA must (by law) have the cold/hot >>friction rating printed on the pad or plate or on the box, but I've never >>found anyone who knew that basic fact. Not even auto parts store workers.

Likewise, all tires have a 4-digit week/year date code on the sidewall,
but I've run into a lot of people who had no idea that it's there, nor
do they know how to read it.

Not only is the date encoded in the serial number of all USA passenger
tires, but the traction, treadwear and temperature (aka speed) of the tire
is embossed on the side.

So is the size (of course) and type (e.g., light truck or radial) and so is
the load range (which is one of the most important specs on every carcass).

Also embossed on the sidewall is the speed (which is separate from the temperature but which is essentially the same metric done a different way).

But how many people can "read" a tire?

I would wager 999 out of 1000 people simply choose tires by whatever
marketing bullshit is fed to them by the tire salesman. Prolly' they buy
tires based on warranty as that's an easy "number line" to choose from.

But if you read a tire, you can easily choose a good tire from a less good
tire (they're all good - but some are more good than others) by the specs.

If there's a tie between two tires of the same specs (which almost never
will happen), then by all means break the tie based on the marketing
warranty.

For those who know how to buy tires, how does this process sound to you?
1. Look at the tires on the car already
2. If you like them - then by all means - buy the same tires
3. But if you don't care and if you're doing a set - then get new ones

a. First figure out the factory specs (speed, load range, size range, etc.)
b. Then limit your search to NOTHING BELOW those minimum specifications!
c. Find the best combination of the factors listed above you care about

Then get the tires that meet your minimum spec at the lowest possible cost.
In general, if you mount the tire yourself, the only extra cost is tax.

Most shipping is free to your home (or to a tire shop).
Mounting and balancing at home is free also (but only after about 10
years).

If you don't plan on living more than ten years, then it's probably not
worth the $300 or so in investment in the tire-changing & balancing tools.
--- Synchronet 3.21d-Linux NewsLink 1.2