Can mix 93 octane and 89 octane make 91, I can or not?

[isekii]

Originally posted by: notfred

Originally posted by: Skoorb

So, if your car only gets 20mpg, you're going to save $75/year. $50/year is more accurate.

Hey, stick that into a long term investment account and half my first kid's college is covered!

I can see your son now...

"dad, can I have a Bicycle?"

"well son, we have to save for the sofa fund, so you can have half a bicycle, and half a pair of roller skates."

ROFL.. that just made my sig list ROFL

Grrrr.. too long wont fit my sig

 

[MomAndSkoorbaby]

Skoorb is now just getting you all going and you are falling for it!

He just wanted to know...we have been and will continue, to put 93 in our car.

 

[StageLeft]

Originally posted by: MrsSkoorb
Skoorb is now just getting you all going and you are falling for it!

He just wanted to know...we have been and will continue, to put 93 in our car.

No we're mixing it as long as the fillup is more than 5 gallons, damnit.

 

[Aves]

Originally posted by: Skoorb

Originally posted by: MrsSkoorb
Skoorb is now just getting you all going and you are falling for it!

He just wanted to know...we have been and will continue, to put 93 in our car.

No we're mixing it as long as the fillup is more than 5 gallons, damnit.

This could get interesting!

 

Well Mrs.Skoorb dropped the ball, Last time I help you out !

 

[BornStar]

Originally posted by: notfred
And where do you live that the gas pump doesn't automatically complete your purchase when you put the nozzle back on the pump?
Put in card, take nozzle, fill car, return nozzle, card is charged. It doesn't assume you're going to use a second nozzle to continue filling the car.

It sounds like he pays inside and has them write down the amount so he can pay both all at once.

 

[MomAndSkoorbaby]

Originally posted by: Roger
Well Mrs.Skoorb dropped the ball, Last time I help you out !

Well, he did originally ask as a legitimate question...then learned that maybe not such a good idea!

He is know just having some fun..bad Skoorbie.

 

[BillGates]

Originally posted by: isekii
just buy higher Octane fuel..

it'll be better for your engine in the long run and youl'l prolly get better gas mileage..

my car requires 91 or 93 i dont remember which.. I just get the best one possible..

Why does everybody think higher octane equals better gas mileage? Read your stupid owner's manual, put in what they recommend, and don't worry about it.

 

[StageLeft]

Originally posted by: MrsSkoorb

Originally posted by: Roger
Well Mrs.Skoorb dropped the ball, Last time I help you out !

Well, he did originally ask as a legitimate question...then learned that maybe not such a good idea!

He is know just having some fun..bad Skoorbie.

The fun started with my comment about the college education. All posts before that were of a truly genuine nature.

 

Damn you people !

Now it's my turn ;

He is know just having some fun..bad Skoorbie.

HA !

 

[Demon-Xanth]

Originally posted by: Roger

Oil on the other hand, just ends up being a half and half mixture and doesn't become homogenous.

Where did you hear this ?

I, on a regular basis mix 80-90 w gear oil with 90-110 w gear oil.
They mix just fine.

Car and Driver actually.

 

They were speaking about motor oil, you should not mix different brands or wieghts because of the viscosity additives and antifoaming agents.

 

[WinkOsmosis]

You can't mix 89 and 93 and get 91. It doesn't work that way. In any case, stop being a cheapskate. Get the damn 93! Or you can go along with your harebrained mixing plan but don't come crying to ATOT when your O2 sensor goes out.

 

[Demon-Xanth]

That's (motor oil) what I was referring to.

 

You can't mix 89 and 93 and get 91. It doesn't work that way. In any case, stop being a cheapskate. Get the damn 93! Or you can go along with your harebrained mixing plan but don't come crying to ATOT when your O2 sensor goes out.

Where are you getting your information from ?

There is no way that mixing gasolines can damage your Oxygen sensor.

That's (motor oil) what I was referring to.

 

[Zenmervolt]

My Quantitative Methods professor does the same thing. And actually, it's what they do at a lot of stations, just inside the pump instead of after the gas gets to your car. See, when you select mid-grade the pump just mixes the proper proportion of high and low grade gas before it reaches the nozzle. As long as you get the proportion right, you can do it. Better to be paying at the pump though, otherwise they look at you funny when you go in to pay with cash.

ZV

 

[Pacfanweb]

Originally posted by: Jellomancer
You can't mix 89 and 93 and get 91. It doesn't work that way. In any case, stop being a cheapskate. Get the damn 93! Or you can go along with your harebrained mixing plan but don't come crying to ATOT when your O2 sensor goes out.

Obviously somebody doesn't know what they're talking about.

Yes, you can mix the two and get 91.

My question is this: Does your car NEED 93 or 91? At what point does it spark knock? I'd use the lowest octane that doesn't make the engine spark knock and roll on.

The vast majority of cars built today need nothing more than 87 octane, and running any higher will actually make them run worse. If your car REQUIRES 91 or 93, then run it. If not, then you're wasting your money, and the oil companies thank you.

 

[StageLeft]

My question is this: Does your car NEED 93 or 91? At what point does it spark knock? I'd use the lowest octane that doesn't make the engine spark knock and roll on.

The vast majority of cars built today need nothing more than 87 octane, and running any higher will actually make them run worse. If your car REQUIRES 91 or 93, then run it. If not, then you're wasting your money, and the oil companies thank you.

That's true - the maxima likes 91. Although it has an anti-knock sensor and will run on 87 a test linked in some other thread a while back showed significant performance drops in cars that required high octane and were given the cheap stuff. It was almost enough to counteract the amount of money saved at the pump by buying cheaper. I think a saab lost 8% or something like that, though most cars the diff won't be nearly so significant.

 

Let me point out a fact for you guys.

The higher the Octane, the harder it is to burn.
The lower the Octane, the easier it is to burn.

When an engine pings or knocks, this is called preignition, it is the uncontrolled burning of petrol in the combustion chamber.
A higher Octane will retard preignition because it has a higher flash point, has more resistance to spontanious ignition and is therefor harder to ignite from the pressures and heat of combustion.

 

[WinkOsmosis]

Originally posted by: Pacfanweb

Originally posted by: Jellomancer
You can't mix 89 and 93 and get 91. It doesn't work that way. In any case, stop being a cheapskate. Get the damn 93! Or you can go along with your harebrained mixing plan but don't come crying to ATOT when your O2 sensor goes out.

Obviously somebody doesn't know what they're talking about.

Yes, you can mix the two and get 91.

My question is this: Does your car NEED 93 or 91? At what point does it spark knock? I'd use the lowest octane that doesn't make the engine spark knock and roll on.

The vast majority of cars built today need nothing more than 87 octane, and running any higher will actually make them run worse. If your car REQUIRES 91 or 93, then run it. If not, then you're wasting your money, and the oil companies thank you.

I'm going on information I read on this forum. I assumed someone who said that it doesn't mix to create an in between octane would know what he was talking about (it was when I asked about putting 93 with the 87 in my tank).

And you SHOULD NOT use the lowest that doesn't cause knock. Are you living in the 60s?? Cars generally don't knock anymore. The ECU alters timing to reduce compression if you use lower octane gas. When I realized that my car needed 91 and not 87, and put in 93, I felt an improvement in response. Besides that, My O2 sensor broke after using 87 for a couple weeks.

(1995 240sx btw. N1SS4N 43VA fo sheezy)

 

And you SHOULD NOT use the lowest that doesn't cause knock. Are you living in the 60s?? Cars generally don't knock anymore. The ECU alters timing to reduce compression if you use lower octane gas. When I realized that my car needed 91 and not 87, and put in 93, I felt an improvement in response. Besides that, My O2 sensor broke after using 87 for a couple weeks.

The ECM does NOT alter compression, it alters ignition timing (Retards it).

Besides that, My O2 sensor broke after using 87 for a couple weeks.

Coincidence only.

We went throught his discussion about Octane quality awhile ago in another one of Skoorb's threads.
Running a lower octane in your vehicle does no harm what so ever as long as the vehicle does not ping.
You will lose a very small amount of power and fuel mileage, but that's it.

 

[Zenmervolt]

If your car doesn't have a knock sensor, use the lowest octane that doesn't knock. If the engine has a knock sensor, use an octane equal to the number recommended in the manual. Yes you can mix the two grades, it's what's done inside the pumps at the gas stations for midgrade.

ZV

 

[WinkOsmosis]

Originally posted by: Roger

And you SHOULD NOT use the lowest that doesn't cause knock. Are you living in the 60s?? Cars generally don't knock anymore. The ECU alters timing to reduce compression if you use lower octane gas. When I realized that my car needed 91 and not 87, and put in 93, I felt an improvement in response. Besides that, My O2 sensor broke after using 87 for a couple weeks.

The ECM does NOT alter compression, it alters ignition timing (Retards it).

Besides that, My O2 sensor broke after using 87 for a couple weeks.

Coincidence only.

Err oops. I know retarding compression is impossible.

Anyway, I recall reading that using the wrong octane IS bad for the O2 sensor. Of course it could be coincidence, but it could not be.


This guy doesn't know what he is talking about, but says that wrong octane is bad for sensors.

 

Anyway, I recall reading that using the wrong octane IS bad for the O2 sensor. Of course it could be coincidence, but it could not be.

I do not want to sound condescending, but I have been working on vehicles for many, many years, and have professional training in the fieled.(A.S.E. Certified Automotive Technician for over twenty years)
When dealing with vehicle problems, you do not guess, you do not assume.
You diagnose and repair vehicles using facts only.
The fact is, you cannot damage an Oxygen sensor by either switching brands of gas, or by using a different octane.
It is physically impossible to do so unless your gasoline was contaminated with lead, silicone or some other chemical that has detrimental effects on a sensor.



No offense, but that guy is full of sh!t, who are you going to believe, an experianced Automotive Technician or that smuck ?

 

[Pacfanweb]

Originally posted by: Jellomancer

Originally posted by: Pacfanweb

Originally posted by: Jellomancer
And you SHOULD NOT use the lowest that doesn't cause knock. Are you living in the 60s?? Cars generally don't knock anymore. The ECU alters timing to reduce compression if you use lower octane gas. When I realized that my car needed 91 and not 87, and put in 93, I felt an improvement in response. Besides that, My O2 sensor broke after using 87 for a couple weeks.

(1995 240sx btw. N1SS4N 43VA fo sheezy)

Yes, you absolutely can and should use the lowest octane that won't knock. And yes, cars most certainly can and do knock these days. ECM's can only retard the timing so much.
Higher mileage cars with lots of carbon build-up can and do knock regardless of how far the ECM retards the timing.

Your O2 sensor would have broken at the same time no matter what gas you were running. A mere coincidence, as Roger stated.

Octane cannot affect the compression ratio, nor can timing.

As always, you should use what your owner's manual SPECIFIES. If my owner's manual tells me I can get a bit more performance from 93, but it's ok to run 87, I'm running 87 unless I'm going to the drag strip.