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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Stock: SP Gap .40 or .54??

  • Thread starter Thread starter madonionrs
  • Start date Start date Apr 19, 2004
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iwashmycar

20+ Year Stangneter
Apr 7, 2004
1,236
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39
Columbus, Ohio
Apr 19, 2004
#21
  • Apr 19, 2004
  • #21
cevtv said:
Well, if the factory opened the gap when they went to a higher output coil, then it makes sense that you could open it a bit with a higher output Accel Supercoil.............
Click to expand...

Makes sense
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
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Massachusetts
Apr 19, 2004
#22
  • Apr 19, 2004
  • #22
5.0guy said:
yeah, I've been wondering about this too--if anyone has a stock car, with the coil cover, look on that, mine is messed up and I couldn't read it. I'm runnin around .04 gap--I think..
Click to expand...


I still have mine. Am I the only one??

On it it reads

Spark Plug Motorcraft AWSF32C 0.052" - 0.056"

This is on an '88. All 87-93's are the same.
 

cevtv

Founding Member
Sep 15, 2002
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Massachusetts
Apr 19, 2004
#23
  • Apr 19, 2004
  • #23
Mustang5L5 said:
All 87-93's are the same.
Click to expand...

Not true. Up to mid '90 the coil output was 40 millijoules, after it was 90 millijoules.

Just use whatever gap works best for your setup.
 

blkstangman88

New Member
Apr 6, 2004
646
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0
Apr 20, 2004
#24
  • Apr 20, 2004
  • #24
dude, ford told me the stock gap is .44, but since i got a msd ignition system there like gap ur spugs at .54, thats is #$%#ed up
 

Legendary

Founding Member
Oct 10, 2002
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City of Angels
Apr 20, 2004
#25
  • Apr 20, 2004
  • #25
I have an MSD ignition and ACCEL coil and I gapped my autolites at .054. After the tune up it didn't feel as good as before and when the car is cold it wants to back fire for the first 5 minutes of driving! I'm not happy.
 

cevtv

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Sep 15, 2002
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Massachusetts
Apr 20, 2004
#26
  • Apr 20, 2004
  • #26
Mine are Autolite 25's gapped at .054" with the stock ignition...........ran like crap gapped at .044".........
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
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Massachusetts
Apr 20, 2004
#27
  • Apr 20, 2004
  • #27
cevtv said:
Not true. Up to mid '90 the coil output was 40 millijoules, after it was 90 millijoules.

Just use whatever gap works best for your setup.
Click to expand...

It still says on the coil cover of my '88 that the gap is 0.052- 0.056"

Yes it's the original cover
 

Luvmy88

New Member
Oct 27, 2003
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Apr 20, 2004
#28
  • Apr 20, 2004
  • #28
This was a pretty cool can of worms to open...

I'm trying .54 tonight.
 
9

90Notch

Founding Member
Jan 31, 2002
1,046
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0
Westwood, MA & yes it's killing me that I'm no
Apr 20, 2004
#29
  • Apr 20, 2004
  • #29
"It still says on the coil cover of my '88 that the gap is 0.052- 0.056"

Yes it's the original cover"

So does my original cover on my 1990 and I've been running 0.054" gap in my 1990 car with stock ignition since new with great results. Might want to recheck that unless cars shipped to MA are different.
 

Legendary

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Oct 10, 2002
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City of Angels
Apr 20, 2004
#30
  • Apr 20, 2004
  • #30
Luvmy88 said:
This was a pretty cool can of worms to open...
Click to expand...

Yeah! I will try the NGK spark plugs next. People seem to like them. Is this a hotter plug? Should I gap it differently (other than .054) for my mods?
 

Mavrick

Founding Member
Aug 29, 2002
2,264
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Collingwood, ON
Apr 20, 2004
#31
  • Apr 20, 2004
  • #31
I gapped mine at .050 tonight, should that be OK with my stock mustang, with a ps91 coil?
 
F

FoxChasis

20+ Year Stangneter
Dec 23, 2003
589
276
93
Apr 20, 2004
#32
  • Apr 20, 2004
  • #32
According to the May 1994 Motorcraft Spark Plugs catalog sitting in front of me:

.054" - '87-'93 (including Cobra)
.050" - '82, '84-'85 (CFI), '86
.044" - '83-'85 (Carb)

According to The Official Ford Mustang 5.0 1979 through 1993 Technical Reference & Performance Handbook:

.050" - '84-'85 (CFI), '86, '93 (Cobra)
.044" - '82-'85 (Carb), '87-'93 (exc. Cobra)
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
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224
Massachusetts
Apr 20, 2004
#33
  • Apr 20, 2004
  • #33
FoxChasis said:
According to the May 1994 Motorcraft Spark Plugs catalog sitting in front of me:

.054" - '87-'93 (including Cobra)
.050" - '82, '84-'85 (CFI), '86
.044" - '83-'85 (Carb)

According to The Official Ford Mustang 5.0 1979 through 1993 Technical Reference & Performance Handbook:

.050" - '84-'85 (CFI), '86, '93 (Cobra)
.044" - '82-'85 (Carb), '87-'93 (exc. Cobra)
Click to expand...

As good as the Official Mustang Handbook is, there have been a few times where i thought i have found mistakes in what they publish. This was one instance. According to the book the gap is 0.044", however as stated, the Vaccuum and Emmissions control decal on my own car lists it as 0.054"
 

Stump1000

New Member
Apr 5, 2003
495
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0
Morristown Tn
Apr 20, 2004
#34
  • Apr 20, 2004
  • #34
closing the plugs up hurts horsepower bad. I let my friend put plugs in my car before we went to the track on night. I got there and it run like ****... pulled the plugs out and he had them gapped at .35. I put them on .52 and the problem was solved
 

Mavrick

Founding Member
Aug 29, 2002
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46
Collingwood, ON
Apr 20, 2004
#35
  • Apr 20, 2004
  • #35
ah so .050 i should be fine.... you guys think? I just dont want to pull all the plugs again and gap them, grease them etc.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
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224
Massachusetts
Apr 20, 2004
#36
  • Apr 20, 2004
  • #36
I would open them up a bit more but that's just me
 
M

madonionrs

New Member
Jun 7, 2003
250
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0
Buffalo NY
Apr 20, 2004
#37
  • Apr 20, 2004
  • #37
Mustang5L5 said:
I would open them up a bit more but that's just me
Click to expand...


Yeah, I had mine at about .44 - .48 and it ran terrible.
I have it now at about .54 - .58 and it runs like a champ.

I would go for low .5xs because you can't be extremely accurate.
 

cevtv

Founding Member
Sep 15, 2002
1,113
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37
Massachusetts
Apr 20, 2004
#38
  • Apr 20, 2004
  • #38
Mustang5L5 said:
As good as the Official Mustang Handbook is, there have been a few times where i thought i have found mistakes in what they publish. This was one instance. According to the book the gap is 0.044", however as stated, the Vaccuum and Emmissions control decal on my own car lists it as 0.054"
Click to expand...


It seems like everywhere you read about it, it says something different. Just use the gap that works best for you!
 

sweet~Low~93

New Member
Oct 26, 2001
637
0
0
Toledo Ohio
Apr 21, 2004
#39
  • Apr 21, 2004
  • #39
FoxChasis said:
The '86 model year H.O. 5.0L Mustang engine spec'd a gap of .045". (The plugs were unique for '86 as well.)
Click to expand...

What's unique about the Plugs -? same you would use on 87-93 5.0's -?

I know the heads are different from 86-e6 -to 87-93 E7's .. 86 5.0's has flat top pistons too.
 
F

FoxChasis

20+ Year Stangneter
Dec 23, 2003
589
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93
Apr 21, 2004
#40
  • Apr 21, 2004
  • #40
The E6SE head requires a unique plug (AWSF_2C). That plug's reach is .708" as opposed to all other years whose plug's reach is .460".
 
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