Octane grade for Subarus

[Cameo]

Do Subarus need premium gas to run?

 

[Tim Conway]

Do Subarus need premium gas to run?

Some do, some don't. My 2000 Forester 169k miles gets by on regular. I had
a 1985 4WD Turbo that needed premium and 20W50 oil! My 1992 Loyale needed
premium when it got old around 150k miles and after.

 

[Cameo]

Some do, some don't. My 2000 Forester 169k miles gets by on regular.
I had a 1985 4WD Turbo that needed premium and 20W50 oil! My 1992
Loyale needed premium when it got old around 150k miles and after.

I wonder what octane ratings are specified in the Owner's Manual of the
latest Legacy and Impreza models (2010 & 2011.)

 

[Frank]

I wonder what octane ratings are specified in the Owner's Manual of the
latest Legacy and Impreza models (2010 & 2011.)

Depends on the model. Legacy here:
http://www.newenglandsubaru.com/Common_inc/Specs/legacy.pdf
Search under "octane"

 

[Dean Hoffman]

Depends on the model. Legacy here:
http://www.newenglandsubaru.com/Common_inc/Specs/legacy.pdf
Search under "octane"

Remember the old days when one could just retard the timing a bit
to get rid of engine ping? A timing light and a wrench to loosen the
distributor were standard tools. So was a matchbook to set the point
and spark plug gap.

 

[Tim Conway]

Depends on the model. Legacy here:
http://www.newenglandsubaru.com/Common_inc/Specs/legacy.pdf
Search under "octane"

Thanks for the link. That's cool. The Legacy 2.5i and the 3.6R both
require regular 87 while the 2.5 GT requires premium 93. I want one. Maybe
a 3.6R. <g>

 

[Cameo]

Thanks for the link. That's cool. The Legacy 2.5i and the 3.6R both
require regular 87 while the 2.5 GT requires premium 93. I want one.
Maybe a 3.6R. <g>

Thanks indeed! I wonder where GT owners find 93 octane gas though. The 3
grades I see around are 87, 89 and 91 octane.

 

[Cameo]

Remember the old days when one could just retard the timing a bit
to get rid of engine ping? A timing light and a wrench to loosen
the distributor were standard tools. So was a matchbook to set the
point and spark plug gap.

I wouldn't want to date myself that far back. ;-)

 

[Dan]

I wouldn't want to date myself that far back. ;-)

Seems like that's the only date I can be sure of anymore and they
sometimes don't work out so well either.

 

[Frank]

Remember the old days when one could just retard the timing a bit to get
rid of engine ping? A timing light and a wrench to loosen the
distributor were standard tools. So was a matchbook to set the point and
spark plug gap.

You got me looking in the bottom of my garage tool box.
Wonder what a timing light and dwell/tach meter are good for these days?
I've also got the old gauge for setting plug gaps which is still good
for my garden equipment.

 

[fourstring]

"Cameo" wrote in message

Thanks for the link. That's cool. The Legacy 2.5i and the 3.6R both
require regular 87 while the 2.5 GT requires premium 93. I want one.
Maybe a 3.6R. <g>

Thanks indeed! I wonder where GT owners find 93 octane gas though. The 3
grades I see around are 87, 89 and 91 octane.

The difference between US and UK fuels' octane rating is interesting.
Our standard supermarket low octane petrol is rated at 95 octane.
We also have 99 octane fuel (+5% bio fuel) easily available which I run my
WRX
on and yes, it does make a difference. Most noticeable is much smoother
running and acceleration from low revs. An overall better performance,
lower consumption and no residue build-up is claimed. On one of the rare
occasions I monitored fuel consumption on a long run I averaged 34 mpg
which surprised the hell out of me!!

-C-
Anything is possible if you don't
know what you're talking about

 

[Dave__67]

     Remember the old days when one could just retard the timing a bit
to get rid of engine ping?    A timing light and a wrench to loosen the
distributor were standard tools.   So was a matchbook to set the point
and spark plug gap.

I've set a few that way...

My 2003 H6 3 liter outback runs best on 93, if you dump in 87 it
detects the ping and retards the timing.


Dave

 

[1 Lucky Texan]

I've set a few that way...

My 2003 H6 3 liter outback runs best on 93, if you dump in 87 it
detects the ping and retards the timing.

Dave

Same here. Indeed some folks say they've done the math both ways and
the decreased mileage when running low octane fuel defeats any cost
savings. Thayt may not be true for all cars or driving styles.

 

[Big Jim]

The majority of cars that "require" premium fuel do just fine without
it. Are people so gullible to think their car won't run on regular
fuel? What if there was none available in the sticks? Use regular and
save a lot a money!

 

[Tim Conway]

The majority of cars that "require" premium fuel do just fine without
it. Are people so gullible to think their car won't run on regular
fuel? What if there was none available in the sticks? Use regular and
save a lot a money!

That's fine with newer cars that automatically adjust the timing with lower
octane fuel. Older cars using below spec fuels can damage the engine with
knocking etc. They will run, but won't be good for the engine.

 

[1 Lucky Texan]

The majority of cars that "require" premium fuel do just fine without
it.  Are people so gullible to think their car won't run on regular
fuel?  What if there was none available in the sticks? Use regular and
save a lot a money!

Yes, most engines equipped with knock sensors or otherwise adjusted
for lower octane will safely run.

But, there are multiple sources of information about tests that
definitively show a DECREASE in fuel efficiency when cars DESIGNED to
utilize high octane fuel are operated with low octane fuel.
Autohaus,wikipedia, Lexus ,edmunds, CNN, etc. basically, retarding the
timing on ANY car will reduce fuel efficiency. And this is how a
vehicle designed for high octane must deal with lower octane to avoid
potential damage from knock - by retarding the timing.

HOWEVER, if your car is designed for low octane(and has no
modifications or problems) - there is absolutely NO advantage to
running high octane fuel.

Check your manual. Trust me, Subaru engineers would LOVE to tell you
your car is designed for low octane, they'd get fewer complaints about
the expense of operating the car. But high compression engines are
less efficient on low octane than the high octane they are designed to
use. You will also enjoy better responsiveness/power using what your
manual suggests.

 

[David]

HOWEVER, if your car is designed for low octane(and has no

modifications or problems) - there is absolutely NO advantage to
running high octane fuel.

Check your manual. Trust me, Subaru engineers would LOVE to tell you
your car is designed for low octane, they'd get fewer complaints about
the expense of operating the car. But high compression engines are
less efficient on low octane than the high octane they are designed to
use. You will also enjoy better responsiveness/power using what your
manual suggests.

My 2008 STi will not run well on regular fuel. The book says 93 octane
and allows for 91 if you have to, but warns of poor performance. I've
tried both. Mileage and performance are MUCH better with the 93. The
car isn't really supposed to be an economical vehicle to drive, but what
are you going to do if you want the kind of punch and power a
turbo-charged 340 whp torque monster can deliver. I LOVE this car!
David

 

[1 Lucky Texan]

My 2008 STi will not run well on regular fuel.  The book says 93 octane
and allows for 91 if you have to, but warns of poor performance.  I've
tried both.  Mileage and performance are MUCH better with the 93.  The
car isn't really supposed to be an economical vehicle to drive, but what
are you going to do if you want the kind of punch and power a
turbo-charged 340 whp torque monster can deliver.  I LOVE this car!
David

Cool. I love my 06 WRX wagon. It's plenty fast enough for an old guy
and it's DL so no problems from cops, kids wanting to race etc. I
ALMOST got an STi but really didn't need the higher insurance. Plus, i
wanted a wagon.

I read where Toyota's 'Lexus College' in Japan tested one of their
vehicles and it dropped 6mpg switching from the recommended high
octane to low.

 

[Cameo]

My 2008 STi will not run well on regular fuel. The book says 93
octane and allows for 91 if you have to, but warns of poor
performance. I've tried both. Mileage and performance are MUCH
better with the 93. The car isn't really supposed to be an economical
vehicle to drive, but what are you going to do if you want the kind of
punch and power a turbo-charged 340 whp torque monster can deliver. I
LOVE this car!

Where do you find 93 octane gas? Here in the Puget Sound area the
highest octane gas I find is 92.

 

[Tim Conway]

Where do you find 93 octane gas? Here in the Puget Sound area the highest
octane gas I find is 92.

I think Amoco used to have 93, but I haven't seen one of them around here in
;a long time (south central PA).