3.0r

[godwhomismike]

subaru gets "hand me down" transmissions

 

I have no complaints about my 5EAT.

 

.

[red beast]

I have no complaints about my 5EAT.

 

.

 

i dont' either

 

 

some are saying the newer version is better.

 

 

 

 

 

remember the 5 speed auto is used in the pathfinder

[jikhead]

You'll lose power if you use 87 octane. The 3.0 is tuned for 91, and 87 will cause detonation, causing timing to be retarded, reducing power. You might as well get a 2.5i if you want to run regular.

 

The 3.6 is tuned for 87.

 

It specifically states in the 08 brochure that the 3.0 can use 87 octance but will lose some hp. Are you sure about the "87 will cause detonation, causing timing to be retarded"?

[SubieDriver]

It specifically states in the 08 brochure that the 3.0 can use 87 octance but will lose some hp. Are you sure about the "87 will cause detonation, causing timing to be retarded"?

 

The ECU monitors for engine knock, or pre-ignition. When that's detected, it retards ignition timing to prevent that pre-ignition. That's one of the reasons why you lose power.

 

You won't necessarily harm the engine by running 87 octane fuel in for a short time, but it's definitely not recommended long-term.

 

Knock is caused when an engine is running too low octane fuel. As the piston goes through the compression stroke, the compression and latent heat in the cylinder causes the fuel to ignite before the spark plug fires, which is why it's called pre-ignition. When it ignites too soon, the piston is still on its way up (before top dead center), and that pre-ignition is trying to push the piston down as it's coming up, which actually slows the piston down and causes some loss of power. It also causes uneven burning within the cylinder, and, if it happens too much, it can cause hot spots, and possibly even burn through your piston. This is not a safe engine condition.

 

Gasoline engines are not designed to run this way, but diesels, on the other hand....

 

So, by running less than the recommended octane, you're running a risk of damaging your engine. I wouldn't advise it.

 

Edited to add: This is why most modern engines have knock sensors, and retard ignition to try to avoid knock. If you have to run 87 octane because the only gas station in the area has nothing better, drive gently until you can find 91 or 93 and refill your tank.

[SubieDriver]

One more thought: Just thinking through this logically, if you truly are getting pre-ignition, retarding the timing won't prevent the pre-ignition, because, by definition, the pre-ignition is not generated by the spark plug, but by the heat and compression of the cylinder, therefore retarding the timing will not eliminate the pre-ignition.

 

It will reduce your power, which *may* reduce the heat generated in the power stroke, thereby causing subsequent heat generation to be reduced, which *may* reduce the likelihood that you'll get more pre-ignition in subsequent power strokes.

 

I would just say to stay away from 87 or 89 octane if your car recommends 91. It's just asking for trouble.

[jpapworth]

I agree, but subaru's are so excellently priced and retain there value so well because they are so reserved with technology and make sure that they make their cars with solid, proven systems that allow the cars to last so long.

 

Do I agree with you? Absolutely! I think nissan has the right idea with either 6 gears or none (CVT). Every manual they have is a 6 speed which is amazing. Sure it costs more, but people still buy them.

 

I think subaru needs to do something different, because their going downhill IMO

 

I don't mean to be spitting venom in the midst of all this "green" talk...but for those of you complaining about not having a CVT, isn't the new diesel legacy going to be CVT? And also have any of you test drove the Maxima's CVT? It is smooth, but its far from sporty and that cars acceleration has suffered because of it. And again, Nissan throws 6 speed trannys at their cars to try and make them quicker. (exception Altima) Even the spec-v isn't that quick.

[red beast]

i'm still amazed that a knock sensor is just a microphone

[tdoggydog]

I saw a lot in this thread about 87 vs. 91 octane. Are you really going to skimp to save a few bucks per fillup? It's probably less than that coffee you buy at Starbuck's.

[SubieDriver]

I saw a lot in this thread about 87 vs. 91 octane. Are you really going to skimp to save a few bucks per fillup? It's probably less than that coffee you buy at Starbuck's.

 

My sentiments exactly. If ya wanna use regular, buy a car that takes regular. If you buy a car that says use 91 octane, then use 91 octane. It's not rocket science.

[Garandman]

I saw a lot in this thread about 87 vs. 91 octane. Are you really going to skimp to save a few bucks per fillup? It's probably less than that coffee you buy at Starbuck's.

I tried to be as scientific as I could with this. had my 3.0R run on a dyno on Regular. I also logged fuel use with regular versus 89 Octane versus 93 for thousands of miles at a time. The engine shows no problems running regular (like detonation) and no difference in mpg. I've logged every gallon of fuel consumed since new, and the car just turned 35K.

 

Maybe it's different where you live but here they sell 87, 89, and 93 at most stations. And the 93 is at least $0.20 per gallon more, and as much as 0.35. That's $3 to $5.25 per fill - for no benefit. Buying one of the Top Tier brands makes more sense than higher octane to me, but I just use Techron on occasion.

[SubieDriver]

I tried to be as scientific as I could with this. had my 3.0R run on a dyno on Regular. I also logged fuel use with regular versus 89 Octane versus 93 for thousands of miles at a time. The engine shows no problems running regular (like detonation) and no difference in mpg. I've logged every gallon of fuel consumed since new, and the car just turned 35K.

 

Maybe it's different where you live but here they sell 87, 89, and 93 at most stations. And the 93 is at least $0.20 per gallon more, and as much as 0.35. That's $3 to $5.25 per fill - for no benefit. Buying one of the Top Tier brands makes more sense than higher octane to me, but I just use Techron on occasion.

 

Thanks for the input. It's somewhat surprising to me. If it runs fine on 87 & 89, why do they specify 91? I suppose they're giving a margin for error, knowing that not all gasolines are created equal.

 

Since you're running a good quality 87, you don't have problems, but running a poorer quality 87 might. Did you try it under hard acceleration? That's when the octane limits are pushed. It might run fine on 87 if you're driving normally, but hard acceleration might generate knock.

[SubieDriver]

By the way VVG, I like the Subaru in your sig.

Pretty cool: スバル

[godwhomismike]

i dont' either

 

some are saying the newer version is better.

 

remember the 5 speed auto is used in the pathfinder

 

 

...and the FX45.

 

 

.

[godwhomismike]

some are saying the newer version is better.

 

 

I really need to test drive one, it's supposed to shift faster and smoother, as well as rev match and blip the throttle.

 

.

[Garandman]

Thanks for the input. It's somewhat surprising to me. If it runs fine on 87 & 89, why do they specify 91? I suppose they're giving a margin for error, knowing that not all gasolines are created equal.

If they're like Nissan, they do it so they can claim another 3-5hp. Our 05 Quest 3.5l has a rating of 242 with 91, 237 with regular.

 

Since you're running a good quality 87, you don't have problems, but running a poorer quality 87 might. Did you try it under hard acceleration? That's when the octane limits are pushed. It might run fine on 87 if you're driving normally, but hard acceleration might generate knock.

Would three full-power pulls on a dyno qualify as "hard acceleration?" That's why I ran it on a dyno first. I did use Premium when I went to the Skip Barber School but it sure didn't feel any different.

 

This is probably the third or fourth time I've copied this SOA message, maybe someone will sticky it in the NA forum.

 

"Aha," you might then say, "But SOA says you have to use Premium." Nope: [emphasis added]

 

Thank you for taking the time to contact us. We hope that you have been enjoying your 2006 Outback 3.0R Wagon.

 

The 3.0-liter H6 engine is designed to operate using unleaded gasoline with an octane rating of 91 AKI or higher. Regular unleaded gasoline with an octane rating of 87 AKI or higher may be used. This is not just for emergency situations. You can use regular unleaded fuel in your vehicle on a regular basis. However, for optimum engine performance and driveability, it is recommended that you use 91 AKI or higher grade unleaded gasoline.

 

You may experience reduced output, poor accelerator response, and reduced fuel economy when using gasoline with an octane rating lower than 91 AKI, depending on your driving habits and conditions.

 

If you experience any of those conditions while using a lower octane rated fuel, you may want to return to using 91 AKI octane rated fuel as soon as possible. Additionally, if your vehicle knocks heavily or persistently, or if you are driving with heavy loads such as when towing a trailer, the use of 91 AKI or higher grade unleaded gasoline is required.

 

Thank you for the opportunity to be of assistance. If you need any future assistance, please feel free to contact us again.

 

Best wishes,

 

John J. Mergen

Subaru of America, Inc.

Customer/Dealer Services Department

[SubieDriver]

If they're like Nissan, they do it so they can claim another 3-5hp. Our 05 Quest 3.5l has a rating of 242 with 91, 237 with regular.

 

Would three full-power pulls on a dyno qualify as "hard acceleration?" That's why I ran it on a dyno first. I did use Premium when I went to the Skip Barber School but it sure didn't feel any different.

 

This is probably the third or fourth time I've copied this SOA message, maybe someone will sticky it in the NA forum.

 

"Aha," you might then say, "But SOA says you have to use Premium." Nope: [emphasis added]

 

Yes, I'd say a dyno run qualifies as hard acceleration. I was not aware of that info from Subaru. I guess it's not as critical as I thought for that particular motor. Thanks for the update. I learned something new today.

[red beast]

You may experience reduced output, poor accelerator response, and reduced fuel economy when using gasoline with an octane rating lower than 91 AKI

 

 

if your saving $3.50- $4.00 per fill, but are using more gas, why bother?

 

 

this is why premium is.... RED BEAST APPROVED:rolleyes:

[Garandman]

if your saving $3.50- $4.00 per fill, but are using more gas, why bother?

How much more gas are you using? People offer all kinds of anecdotes but don't have any data to support their opinion. Most people seem to check mileage only occasionally, and only when it's really good: I have a friend who says he "averages" 18 mpg in a Chevy Suburban.

 

If I can save money with higher octane I'm all for it. I switched back and forth between regular and 93 (they don't sell 91 around here) for 2,000 miles at a time - roughly six tanks per trial. I did this for 6,000 miles when I simply gave up because there didn't seem to be difference. That was from about 2,000 to about 8,000 miles.

 

Here's a graph from the first 20,000 miles. I've continued to log fuel use, I'll update it soon as we now have 35,000 miles on it.

 

For the first 5,000 miles we averaged 19.9 mpg.

For 5-10,000 mi we averaged 21.3.

For 10-15,000 we averaged 22.3.

For 15-20,000 we averaged 23.2.

 

I live in Boston and most of my driving that isn't city is commuting. So most people would do better than this.

 

One caveat: this graph weights each tank average the same, even though one might have been a fill from half, and another from empty. The numbers above reflect the true average: miles traveled divided by gallons used.

[red beast]

are you that hard up that spending an extra $3.50-$4.00 per fill will kill your budget?

 

and your losing a little extra power.

[Garandman]

For reference, here's the updated info for 35,189 miles.

 

The average since I bought the car is 20.9 mpg.

For 25-35K it was 20.6. The new formulations seem to deliver lower mileage but I don't have anything to support that other than our fleet use (five vehicles).

 

I have used 93 and 89 octane at times, but mostly regular. There have been four different tires used during this time: the stock Bridgestones, Nokian RSI snows for part of two seasons, Nokian WR's from last February to May, and Goodyear F1 GS D3's for the last two summers. Nothing else has changed. I'll be curious what the dyno shows after 35K of use.

 

I haven't driven as much this summer as I try to ride my motorcycle whenever I can - it usually gets over 50mpg on regular commuting the same routes.

[red beast]

it's too early in the morning to be anal retentive.

 

 

 

 

 

 

 

 

For reference, here's the updated info for 35,189 miles.

 

The average since I bought the car is 20.9 mpg.

For 25-35K it was 20.6

 

I have used 93 and 89 octane at times, but mostly regular.

There have been four different tires used during this time: the stock Bridgestones, Nokian RSI snows for part of two seasons, Nokian WR's from last February to May, and Goodyear F1 GS D3's for the last two summers.

 

I haven't driven as much this summer as I try to ride my motorcycle whenever I can - it usually gets over 50mpg on regular commuting the same routes.

[Garandman]

Wow, I've never been called that before. So I looked it up.

 

The term is often used in a derogatory sense to describe a person with such attention to detail that it becomes an annoyance to Red Beast.

 

This is pretty funny since the opposite condition - making statements without any factual basis - is called "Talking out of your ass."

[red beast]

like i said at the time it was too early in the morning for detail when i was "generally speaking"

 

 

i'm not a "morning person"

 

matter of fact i'm not a "midday" person either....

 

 

nor an "afternoon" one.

 

 

Conversationally, the term is often used to describe a person deemed to be overly obsessed with minor details. Its roots are said to be from Sigmund Freud.

 

The term is often used in a derogatory sense to describe a person with such attention to detail that the obsession becomes an annoyance to others, and can be carried out to the detriment of the so-called anal-retentive person.

 

 

 

 

http://en.wikipedia.org/wiki/Anal_retentive