• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

Will it hurt my engine or not?

Joined
Aug 9, 2007
Messages
425
Reaction score
13
Points
18
Location
Lawrenceburg, IN
Vehicle Year
2008
Make / Model
Ford
Engine Type
2.3 (4 Cylinder)
Transmission
Manual
2WD / 4WD
2WD
My 2008 Ranger 2.3L is recommended to run on 87 octane gas and have been wondering IF using 89 octane or maybe 93 octane gas for one full tank of gas will hurt it in any way? The engine has almost 189,000 miles on it.
 


scotts90ranger

Well-Known Member
RBV's on Boost
Joined
Feb 28, 2001
Messages
6,298
Reaction score
1,707
Points
113
Location
Dayton Oregon
Vehicle Year
1990, 1997
Make / Model
Ford
Engine Type
2.3 (4 Cylinder)
Engine Size
2.3 Turbo
Transmission
Manual
2WD / 4WD
4WD
Total Lift
6
Tire Size
35"
No, it only hurts going the other way around, if premium is recommended then regular can hurt sometimes...
 

lil_Blue_Ford

Well-Known Member
Forum Moderator
V8 Engine Swap
TRS 20th Anniversary
TRS Event Participant
Joined
Aug 6, 2007
Messages
6,281
Reaction score
2,474
Points
113
Location
Butler, PA, USSA
Vehicle Year
95
Make / Model
Ford
Engine Size
4.9L
Transmission
Manual
Yup. I’ve actually seen some 87 vehicles gain in mpg running 89. Sometimes it was worth it to pay a little more and sometimes it wasn’t, so it wasn’t a huge gain
 

RonD

Well-Known Member
Joined
Jun 2, 2012
Messages
22,427
Reaction score
5,588
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
If your engine has compression ratio of 9.4:1 or higher then running 89/91 octane can increase MPG and performance

The 2.3l Duratec looks to be 9.7:1, so it will have a Knock Sensor that allows it to run 87 octane with no issues

Driving around town I doubt you would notice any difference between 87 or 91 octane, on a longer road trip yes, would get better MPG, but higher cost for fuel, lol

Knock sensor allows computer to adjust spark timing to prevent lower octane Knock/Ping as it occurs
And this reduces power, so reduces MPG, but its not alot
 

gw33gp

Well-Known Member
U.S. Military - Veteran
TRS Banner 2010-2011
Ham Radio Operator
Joined
Aug 7, 2007
Messages
1,500
Reaction score
258
Points
83
Location
Costa Mesa, CA
Vehicle Year
2002
Make / Model
Ford
Engine Type
4.0 V6
Engine Size
4.0 SOHC
Transmission
Manual
2WD / 4WD
4WD
Tire Size
33"
The main thing it will hurt is you wallet. I have heard you can get a little carbon build up using higher octane fuel than needed, but one tank would not be a problem. As RonD indicated, your compression ratio is high enough that you could benefit from it in gas mileage and possibly even a little in performance.
 

Blmpkn

Well-Known Member
Supporting Member
Joined
Feb 15, 2020
Messages
3,323
Reaction score
2,952
Points
113
Location
Southern maine
Vehicle Year
2021
Make / Model
Ford ranger
Engine Type
2.3 EcoBoost
Engine Size
2.3
Transmission
Automatic
2WD / 4WD
4WD
Total Lift
2.5" level
Tire Size
275/65/18
My credo
Its probably better to be self deprecating than self defecating.
The main thing it will hurt is you wallet. I have heard you can get a little carbon build up using higher octane fuel than needed, but one tank would not be a problem. As RonD indicated, your compression ratio is high enough that you could benefit from it in gas mileage and possibly even a little in performance.
Higher octane fuels burn slower and somewhat incomplete in low CR motors, the incompleteness of the burn is where the extra carbon comes from.
 

RonD

Well-Known Member
Joined
Jun 2, 2012
Messages
22,427
Reaction score
5,588
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
Octane is a heat rating
A gallon of 87 octane and a gallon of 93 octane have the same energy stored

Its how the energy is released and used that makes the difference, the efficiency of the conversion
Gasoline engines are 25% efficient
If a gallon of gas costs $4 then $1 pushes you down the road, $3 is used to heat up the engine and air around it
SUCKS don't it, lol

Newer gasoline engine designs are pushing close to 30% to 35%

Diesels were 30% to 35% and now pushing 40% to 45%

Electric vehicles are 85-90%




Simple explanation of octane rating, not scientific just an explanation
Oct = 8
Tane = carbon chain

Octane molecule of 8 carbon atoms is very stable hard to break part, ignite
Shorter carbon chains are more volatile, easier to break apart, ignite

87 octane has 87% 8 chain carbons so 13% shorter chains
89 octane has 89% 8 chain carbons so 11% shorter chains
91 octane has 91% 8 chain carbons so 9% shorter chains
93 octane has 93% 8 chain carbons and 7% shorter chains

The 87 octane will be more likely to self ignite during compression stroke, and that causes pinging/knocking noise that you can hear, and this also causes cylinder damage so its a bad thing, lol
Knock sensors detect this(before you can hear it) and computer will advance the spark timing to prevent it, this means "full explosive" ignition will not occur at the optimal time on power stroke for best power

Compression generates heat so the higher the compression ratio the more likely self ignition becomes

89/91/93 octane fuels are less likely to self ignite, but still can if heated up high enough

A gallon of any gasoline has the same number of carbon atoms, so same potential energy, its just the configuration of those carbon atoms that decides Octane rating

Obviously since there are fuels with over 100 octane the percentage thing is just used as a example of "how it works" :)
 
Last edited:

scotts90ranger

Well-Known Member
RBV's on Boost
Joined
Feb 28, 2001
Messages
6,298
Reaction score
1,707
Points
113
Location
Dayton Oregon
Vehicle Year
1990, 1997
Make / Model
Ford
Engine Type
2.3 (4 Cylinder)
Engine Size
2.3 Turbo
Transmission
Manual
2WD / 4WD
4WD
Total Lift
6
Tire Size
35"
Only thing I can throw at what Ron just posted is the knock sensors RETARD the spark advance, not advance, but yeah, didn't have it in me to expand last night :)

Pre ignition is bad, cast pistons start to wear away until they burn into the ring lands, forged pistons are more forgiving but knock is never a good thing...
 

RonD

Well-Known Member
Joined
Jun 2, 2012
Messages
22,427
Reaction score
5,588
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
You can't say that, spark is "differently abled" is the correct term
 

dvdswan

Well-Known Member
U.S. Military - Veteran
Joined
Feb 11, 2021
Messages
2,047
Reaction score
1,617
Points
113
Location
Seattle, WA
Vehicle Year
1991
Make / Model
Ranger XLT 2WD
Engine Type
3.0 V6
Transmission
Automatic
2WD / 4WD
2WD
My credo
Keep your mind like an umbrella, it only works if its open... Continually learning.
You can't say that, spark is "differently abled" is the correct term
I think we need to ban @RonD for making a new gender label... :ban:
 

pjtoledo

Well-Known Member
Supporting Member
U.S. Military - Veteran
Joined
Oct 5, 2007
Messages
4,100
Reaction score
1,538
Points
113
Location
Toledo Ohio
Vehicle Year
20002005199
Make / Model
Fords
Engine Size
3.0 2.3
My credo
get outta my way, I'm falling!
fun for all quest

how do you define cetane?
 

dvdswan

Well-Known Member
U.S. Military - Veteran
Joined
Feb 11, 2021
Messages
2,047
Reaction score
1,617
Points
113
Location
Seattle, WA
Vehicle Year
1991
Make / Model
Ranger XLT 2WD
Engine Type
3.0 V6
Transmission
Automatic
2WD / 4WD
2WD
My credo
Keep your mind like an umbrella, it only works if its open... Continually learning.
cetane, as octane is for gas, cetane is for electric cars. "C" batteries. no?

how about,

cetane fuel for the 7 seas... no?

IIRC, it's something to do with diesel fuel compression.
 

duffy

Member
Joined
Sep 26, 2020
Messages
93
Reaction score
17
Points
8
Location
Hot Springs, SD
Vehicle Year
1989
Make / Model
Ford Bronco II
Transmission
Automatic
Cetane is the octane equivalant in diesel.......
 

Bill

Well-Known Member
Joined
Aug 6, 2007
Messages
879
Reaction score
594
Points
93
Location
Sacramento, CA
Vehicle Year
2007
Make / Model
Ford Ranger
Engine Type
2.3 (4 Cylinder)
Transmission
Manual
2WD / 4WD
2WD
Driving around town I doubt you would notice any difference between 87 or 91 octane, on a longer road trip yes, would get better MPG, but higher cost for fuel, lol
I really don't think it is going to make a difference in fuel economy unless there is a load placed on the engine such as towing or driving uphill, but not for normal freeway cruising where the same speed is maintained.
 

scotts90ranger

Well-Known Member
RBV's on Boost
Joined
Feb 28, 2001
Messages
6,298
Reaction score
1,707
Points
113
Location
Dayton Oregon
Vehicle Year
1990, 1997
Make / Model
Ford
Engine Type
2.3 (4 Cylinder)
Engine Size
2.3 Turbo
Transmission
Manual
2WD / 4WD
4WD
Total Lift
6
Tire Size
35"
It all depends on cylinder pressure... in some boat engines at work (GM 6.2L direct injection, high compression ratio... like 11.2) we "recommend" premium, but there's two spark tables that it learns between with the knock sensors so it doesn't hurt the engine in theory, in those the WOT engine speed can change as much as 200rpm which if you look at the impeller curves (jet boats, impeller not propeller...) is above insignificant... On the 4.3L DI and 5.3L DI engines it isn't as big of a difference even though the compression ratio is still like 10.5:1
 

Sponsored Ad


Sponsored Ad

Top