[ARCHIVED THREAD] - 93 Octane (Page 1 of 2)
Posted: 4/1/2012 9:29:20 PM EDT
|
You use it much?
I try to fill up a tank every 5th or so stop, but today, doing it, with the difference being between $3..79 and $4.09, it was painful to consider.....though really, for my tank, it was just $3.30 more. When I was young and gas was cheap and I was more unaware of the value of money, I would do it all the time. But now..... ____________________________________________________________________________ ("When I was young and in my prime, I use to g***b*** all the time. But now that I'm old and turning gray, I only g***b*** once a day!"––lyrics, (w,stte), old military song) |
|
If your engine doesn't need high octane, YOU GET NOTHING FROM USING IT. NOTHING.
Octane rating is about preventing compression ignition, "detonation", where the fuel air mixture explodes prematurely. This is referred to as 'knock'. It is bad. High compression ratio engines, and forced induction usually require high octane gas. Most naturally aspirated cars are tuned to use 87. |
|
Quoted: You use it much? I try to fill up a tank every 5th or so stop, but today, doing it, with the difference being between $3..79 and $4.09, it was painful to consider.....though really, for my tank, it was just $3.30 more. When I was young and gas was cheap and I was more unaware of the value of money, I would do it all the time. But now..... ____________________________________________________________________________ ("When I was young and in my prime, I use to g***b*** all the time. But now that I'm old and turning gray, I only g***b*** once a day!"––lyrics, (w,stte), old military song) only use higher octane if you have to. |
|
Quoted:
Whatcha driving ? Subaru Forester, 02. __________________________________________________ ("........Baby you can drive my car, Yes I'm gonna be a star, Baby you can drive my car, And maybe I'll love you....", lyrics, (w,stte), "Drive my car" by the Beatles) |
|
Quoted:
Quoted:
Whatcha driving ? Subaru Forester, 02. __________________________________________________ ("........Baby you can drive my car, Yes I'm gonna be a star, Baby you can drive my car, And maybe I'll love you....", lyrics, (w,stte), "Drive my car" by the Beatles) My 01 Outback does just fine on 87 with regular oil / filter changes with good oil and filters. |
| I don't know why people do this, or rather why misinformation keeps being spread. Essentially the higher the octane rating the harder the fuel is to ignite, that is all. It is designed for higher compression motors and those with some form of forced induction (superchargers, turbochargers). This is to avoid pinging otherwise known as pre-ignition or knocking, which will damage motors. If you have low compression naturally aspirated motor there is absolutely no point in using higher octane .Use what the manufacturer recommends. On older cars where you could set the spark advance yourself you could normally advance the ignition timing a little bit and use higher octane fuel to gain a little bit of hp. If you are asking if you should use higher octane fuel this doesn't apply to you though. |
|
Quoted:
Quoted:
I have a turbo too, I get about 5 mpg better and the car runs better. Pluss I need non ethanol fuel. I wish I could find non-ethanol fuel anywhere near me... Everything here has the corn liquor in it these days. It is very hard to find non ethanol fuel in MN where I work, but it is pretty easy to find in WI, where I live. If you can find it in MN it is about 50 cents higher than regular. In WI it is usually 30 cents higher. |
|
Quoted:
I don't know why people do this, or rather why misinformation keeps being spread. Essentially the higher the octane rating the harder the fuel is to ignite, that is all. It is designed for higher compression motors and those with some form of forced induction (superchargers, turbochargers). This is to avoid pinging otherwise known as pre-ignition or knocking, which will damage motors. If you have low compression naturally aspirated motor there is absolutely no point in using higher octane .Use what the manufacturer recommends. On older cars where you could set the spark advance yourself you could normally advance the ignition timing a little bit and use higher octane fuel to gain a little bit of hp. If you are asking if you should use higher octane fuel this doesn't apply to you though. |
|
Quoted:
Quoted:
Whatcha driving ? Subaru Forester, 02. __________________________________________________ ("........Baby you can drive my car, Yes I'm gonna be a star, Baby you can drive my car, And maybe I'll love you....", lyrics, (w,stte), "Drive my car" by the Beatles) Well how about that. Same car is in the garage. If it has a knock, it has nothing to do with fuel. Putting premium fuel in the car is doing nothing but flushing money down the toilet. The dreaded Subaru piston slap that was a bad design in those engines is impossible to eliminate unless you do a piston upgrade. Subaru designers felt that eliminating the piston skirts in those engines would reduce cylinder wall drag and increase power and economy. They went into total brain-lock with the idea and forgot about metal expansion and contraction at different temperatures. My knock sensor sends a code and lights up the CEL when the OAT gets below freezing. Subaru will do nothing about it. The car has 68,000KMS. |
|
Quoted:
If your engine doesn't need high octane, YOU GET NOTHING FROM USING IT. NOTHING. Octane rating is about preventing compression ignition, "detonation", where the fuel air mixture explodes prematurely. This is referred to as 'knock'. It is bad. High compression ratio engines, and forced induction usually require high octane gas. Most naturally aspirated cars are tuned to use 87. Most, like mine say 87 "MINIMUM", my 4runner runs better on 93. I've been running 89 for the past few tanks and it hasn't ran as well. I get slightly better power and mpg with 93. Is it worth the extra 20-30 cents per gallon? For me it is. |
|
Quoted:
Quoted:
If your engine doesn't need high octane, YOU GET NOTHING FROM USING IT. NOTHING. Octane rating is about preventing compression ignition, "detonation", where the fuel air mixture explodes prematurely. This is referred to as 'knock'. It is bad. High compression ratio engines, and forced induction usually require high octane gas. Most naturally aspirated cars are tuned to use 87. Most, like mine say 87 "MINIMUM", my 4runner runs better on 93. I've been running 89 for the past few tanks and it hasn't ran as well. I get slightly better power and mpg with 93. Is it worth the extra 20-30 cents per gallon? For me it is. SOME modern cars 'computers will take advantage of higher octane by advancing the ignition timing as long as it doesn't start knocking. But running 93 octane once every 5 tanks is pointless. |
|
Quoted:
If your engine doesn't need high octane, YOU GET NOTHING FROM USING IT. NOTHING. Octane rating is about preventing compression ignition, "detonation", where the fuel air mixture explodes prematurely. This is referred to as 'knock'. It is bad. High compression ratio engines, and forced induction usually require high octane gas. Most naturally aspirated cars are tuned to use 87. As noted, some modern cars/trucks will see performance gains by using high octane fuel even though it doesn't "need" it. |
|
Quoted:
Quoted:
Quoted:
If your engine doesn't need high octane, YOU GET NOTHING FROM USING IT. NOTHING. Octane rating is about preventing compression ignition, "detonation", where the fuel air mixture explodes prematurely. This is referred to as 'knock'. It is bad. High compression ratio engines, and forced induction usually require high octane gas. Most naturally aspirated cars are tuned to use 87. Most, like mine say 87 "MINIMUM", my 4runner runs better on 93. I've been running 89 for the past few tanks and it hasn't ran as well. I get slightly better power and mpg with 93. Is it worth the extra 20-30 cents per gallon? For me it is. SOME modern cars 'computers will take advantage of higher octane by advancing the ignition timing as long as it doesn't start knocking. But running 93 octane once every 5 tanks is pointless. Mine is 25 years old. All I know is that since I've started using the higher ocatne it knocks and pings less, gets better MPG and just runs better in general. I've tracked teh data for 7 years now. |
|
Quoted:
Quoted:
If your engine doesn't need high octane, YOU GET NOTHING FROM USING IT. NOTHING. Octane rating is about preventing compression ignition, "detonation", where the fuel air mixture explodes prematurely. This is referred to as 'knock'. It is bad. High compression ratio engines, and forced induction usually require high octane gas. Most naturally aspirated cars are tuned to use 87. As noted, some modern cars/trucks will see performance gains by using high octane fuel even though it doesn't "need" it. Those would only be engines that 'self detune' so they don't knock using lower octane fuels. An engine rated for 87 gets absolutely bupkiss out of using higher octane fuels. |
|
Quoted:
Quoted:
I have a turbo too, I get about 5 mpg better and the car runs better. Pluss I need non ethanol fuel. I wish I could find non-ethanol fuel anywhere near me... Everything here has the corn liquor in it these days. Pure Gas OH Sir James... |
|
Quoted:
Quoted:
I try to fill up a tank every 5th or so Using higher octane than your car requires is not a "treat" for your engine and provides no benefit. Use what the manufacturer says, no more, no less. +1 It never ceases to amaze me that people see things like recommended fuels, fluids, and lubricants and think, "Those silly engineers, always telling me to use the wrong stuff! I know better!" |
|
Quoted:
Quoted:
Quoted:
I have a turbo too, I get about 5 mpg better and the car runs better. Pluss I need non ethanol fuel. I wish I could find non-ethanol fuel anywhere near me... Everything here has the corn liquor in it these days. Pure Gas OH Sir James... I'm curious how any of these stations know whether or not the distributor is putting ethanol in their fuel. |
|
93 octane is like assault fuel in California... 91 is all we can get, with the exception of a handful of stations that offer race fuels.
And my car recommends 89 or higher, I use 91 since I premix the fuel (rotary). Cheap insurance since detonation can really screw up this engine. |
|
Quoted:
93 in my 2002 Miata. Manual specifies 91, but they don't sell that in Ohio. It'll run on 87, but it pings under load before the ECU backs the timing off. Mileage suffers, too. It's not even $5 difference on a fill-up, so 93 it is. Around me Sonoco has 91 octane. |
|
For those in MN/WI here is a list of stations the MSRA puts out |
|
Quoted:
If your engine doesn't need high octane, YOU GET NOTHING FROM USING IT. NOTHING. Octane rating is about preventing compression ignition, "detonation", where the fuel air mixture explodes prematurely. This is referred to as 'knock'. It is bad. High compression ratio engines, and forced induction usually require high octane gas. Most naturally aspirated cars are tuned to use 87. This. Most people have no clue about this. Just yesterday my neighbor was telling me she wanted 93 for her lawnmower so it would run better. I had to convince her otherwise. |
|
Quoted:
Quoted:
If your engine doesn't need high octane, YOU GET NOTHING FROM USING IT. NOTHING. Octane rating is about preventing compression ignition, "detonation", where the fuel air mixture explodes prematurely. This is referred to as 'knock'. It is bad. High compression ratio engines, and forced induction usually require high octane gas. Most naturally aspirated cars are tuned to use 87. This. Most people have no clue about this. Just yesterday my neighbor was telling me she wanted 93 for her lawnmower so it would run better. I had to convince her otherwise. Lawnmowers actually do run better on higher octane from what I've heard. Don't know if it's true or not. |