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Anyone have any comments about 87 vs 91 octane?

  • Thread starter Thread starter v8thunder1
  • Start date Start date Dec 17, 2003
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v8thunder1

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Dec 7, 2003
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Dec 17, 2003
#1
  • Dec 17, 2003
  • #1
I just wanted to know what people are running in their GT's. Pros/Cons?
 
S

Satin Silver GT

Member
Jul 12, 2003
127
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16
Sagamore Ma.
Dec 17, 2003
#2
  • Dec 17, 2003
  • #2
I run 87 in my 2002 GT with out any problems. Ford recommends 87 octane in the owners manual. Spoke with the Service Manager and he confirmed 87.

2002GT 5 spd
AutoMeter Lunar Gauge cluster
Hurst Billet Plus shifter
K&N
Magnaflow Cat back
 

COBRA90GT

Mustang Master
Sep 22, 2001
6,654
0
87
HOCKEYTOWN ® , MI
Dec 17, 2003
#3
  • Dec 17, 2003
  • #3
Stick with the regular stuff unless you have advanced the timing and/or NEED the higher octane gasoline (ie. car pings with 87, but not with 89).
 
D

DC-GT

New Member
Nov 25, 2003
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Dec 17, 2003
#4
  • Dec 17, 2003
  • #4
COBRA90GT said:
Stick with the regular stuff unless you have advanced the timing and/or NEED the higher octane gasoline (ie. car pings with 87, but not with 89).
Click to expand...

Bulllseye!

Your mods will eventually cause you to need higher octane or a tune. I use premium once in a while just because it has more detergents in it to clean my valve train and injectors. I don't run it all the time because I don't want the detergents to mess with my injector seals.

Wow, that seemed confusing, lol.

Bo
 

Beau

Founding Member
Jan 29, 2000
3,050
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0
San Diego
Dec 17, 2003
#5
  • Dec 17, 2003
  • #5
for every 4 tanks of 87, i fill it with 1 tank of 91. i figure that as soon as i get any serious engine work done, i'll have to use 91 but until then i am going to save money
 

downsouthman1

Member
Dec 16, 2003
643
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16
Texas
Dec 17, 2003
#6
  • Dec 17, 2003
  • #6
Satin Silver GT said:
I run 87 in my 2002 GT with out any problems. Ford recommends 87 octane in the owners manual. Spoke with the Service Manager and he confirmed 87.

2002GT 5 spd
AutoMeter Lunar Gauge cluster
Hurst Billet Plus shifter
K&N
Magnaflow Cat back
Click to expand...
The manual does advise 87 oct. I did however, have a Superchip installed on my car. Before I had it done they told me I'd have to run 93 octane. I was in disbelief so I ran 87 the next time @ the pump after installation & my car bogged down to like 150 RPMs a lot. So during my next trip to the pump I ran 93 & have done so ever since & it's fine now.
 

JonJon

Founding Member
Aug 16, 2002
4,801
1
68
back in Marylands
Dec 17, 2003
#7
  • Dec 17, 2003
  • #7
87.
 

'96&'01Stang

New Member
Feb 10, 2003
798
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Georgia
Dec 17, 2003
#8
  • Dec 17, 2003
  • #8
I run 93 octane
 
J

jimfitzgerald

New Member
Apr 11, 2001
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Dec 17, 2003
#9
  • Dec 17, 2003
  • #9
You should run 87 unless you have advanced timing or get pinging. Then you should up the octane. Running higher octane than you need will not give you more power, and may actually reduce power because it is more stable and harder to ignite.
 

AdRock

Member
Nov 13, 2003
521
1
19
South Texas
Dec 17, 2003
#10
  • Dec 17, 2003
  • #10
I ran 87, then 89, then 93. My car seems to like the 89 the best. It ran the same with 87 or 93 but feels like it has a little more pep with the 89.
 

Jesus

Banned
May 13, 2003
267
0
0
Woodland Hills, CA
Dec 17, 2003
#11
  • Dec 17, 2003
  • #11
I too am running 89 in my car. I have a Steeda T/A set at 13* and tried 91, but the car didnt run as well as it does with 89. I havent been able to detect any pinging. I have tried to get it to ping by accelerating under load (going up hills in 5th) and havent heard a thing. Car just feels stronger with 89, and it doesnt hesitate off the line like it did with 91.
 

19mustangGT97

New Member
Feb 12, 2003
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Foster City, CA
Dec 17, 2003
#12
  • Dec 17, 2003
  • #12
I dont get it, my 97 pings on 87 and 89 and sometimes pings at night on 91 with my cutouts open. Before I had my cutouts and only mods being flows and a filter it would ping pretty bad on 87 and 89. Don't know what my manual says but it seems it should be the same as 99+. Does anyone know why I ping on 87?
 
J

jimfitzgerald

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Apr 11, 2001
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Dec 17, 2003
#13
  • Dec 17, 2003
  • #13
19mustangGT97 said:
I dont get it, my 97 pings on 87 and 89 and sometimes pings at night on 91 with my cutouts open. Before I had my cutouts and only mods being flows and a filter it would ping pretty bad on 87 and 89. Don't know what my manual says but it seems it should be the same as 99+. Does anyone know why I ping on 87?
Click to expand...
Maybe the mixture is too lean or too much timing.
 

19mustangGT97

New Member
Feb 12, 2003
122
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0
Foster City, CA
Dec 17, 2003
#14
  • Dec 17, 2003
  • #14
Yea but I have done nothing to my timing.. Everything was stock except the mufflers and filter and now the only thing new is the cutouts but I still ping on 87 with them open.
 

2000GTnoExtras

Founding Member
Apr 2, 2002
990
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Rocklin
Dec 18, 2003
#15
  • Dec 18, 2003
  • #15
19mustangGT97 said:
Yea but I have done nothing to my timing.. Everything was stock except the mufflers and filter and now the only thing new is the cutouts but I still ping on 87 with them open.
Click to expand...
I would try replacing fuel filter, spark plugs (copper) and then resetting the ECU. You may wanna inspect your wires too.
Then fill it up with 87 and see what happens.

I put like $10.00 of 91 in my car every couple months, run 87 all the rest of the time.
 

GreekStang85

Member
Jun 11, 2003
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Dec 18, 2003
#16
  • Dec 18, 2003
  • #16
i usually choose 89 and every once in a while ill go with 93
 

ASilver2001GT

Founding Member
Jun 2, 2002
636
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0
Huntsville/Birmingham, AL
Dec 18, 2003
#17
  • Dec 18, 2003
  • #17
I run 93
 
T

TripleBlk

Member
Nov 12, 2002
312
3
19
Cape Canaveral FL
Dec 18, 2003
#18
  • Dec 18, 2003
  • #18
v8thunder1 said:
I just wanted to know what people are running in their GT's. Pros/Cons?
Click to expand...
I run 87 now. When the car (99GT) was new, I was pinging out of the gate in tollbooths(I don't have to stop, I have one of those electronic passes), so I burned 93 octane until I learned the car wouldn't ping if I dropped it down into 3rd or second (duh). 87 works for me fultime now.
 

NFCStang

New Member
Oct 3, 2003
127
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Taking a leak in an SRT-4 gas tank
Dec 18, 2003
#19
  • Dec 18, 2003
  • #19
I seem to get better milage with 93 but I don't notice a power difference between that and 87-89
 

340.29m/s

New Member
Sep 22, 2003
213
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0
Blue Springs, Mo
Dec 18, 2003
#20
  • Dec 18, 2003
  • #20
I think everyone has pretty much said it, run 87 unless you begin to ping.

Cobras, Machs, and FI'd Mustangs on the other hand should run ATLEAST 91 octane (that is all we have around here)
 
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