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spark plug gap for headswapped cars

  • Thread starter Thread starter RysRed96GT
  • Start date Start date Nov 13, 2004
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RysRed96GT

I like it FURRY!!!
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Nov 13, 2004
#1
  • Nov 13, 2004
  • #1
i heard in another thread that a smaller gap size, like .40ish, would make more power. supposably another guy in the thread confirmed it but i want to make sure. would i make more power with a smaller gap with my higher compression?
 

tomustang

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#2
  • Nov 13, 2004
  • #2
well i played with this theroy since i had a problem with a cyl misfire. i went from the stock .50 something gap to a .40. i felt a real noticable gain. i recommend it.

the misfie actually came from a cracked plug wire
 
H

HIGDON

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Nov 2, 2003
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Nov 13, 2004
#3
  • Nov 13, 2004
  • #3
Mine will be set at .40 when I fire it up tomorrow. I did this with a set of autolites prior to this it is possible I felt a gain, but I wasn't looking for one. . .just trying to keep the plugs from fouling.
 

RysRed96GT

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#4
  • Nov 13, 2004
  • #4
sweet, i'll try it too. now for an old classic question: should i get copper or platinum?
 

CanadaStang

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#5
  • Nov 13, 2004
  • #5
I had done some research on this when I did my headswap. Found a few threads on here saying .40 is the way to go. But checking over MD, the general consensus is to leave it at .54 I don't know of anyone doing any dyno test with the different gaps.
As to wether to go with copper or platnum, rumour has it, copper is the way to go.
 

RysRed96GT

I like it FURRY!!!
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#6
  • Nov 13, 2004
  • #6
well i've been hearing more about .40, so i might do that for the hell of it.
 

onesticker

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Nov 13, 2004
#7
  • Nov 13, 2004
  • #7
I have mine gapped at .35 but I have a blower. I've heard from many people that .40 is the way to go on swapped heads. Stick with copper plugs. The platinum may hive you detonation problems. I'm running Motor craft 12c's which are 2 heat ranges cooler.
 

CanadaStang

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#8
  • Nov 13, 2004
  • #8
RysRed96GT said:
well i've been hearing more about .40, so i might do that for the hell of it.
Click to expand...
Yup!! I think thats what you should do. Yup, most definitly. And then, eh hmm, if it's no trouble, could ya let me know how she runs.
 

RysRed96GT

I like it FURRY!!!
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#9
  • Nov 13, 2004
  • #9
CanadaStang said:
Yup!! I think thats what you should do. Yup, most definitly. And then, eh hmm, if it's no trouble, could ya let me know how she runs.
Click to expand...
i'll do it tommorrow after i put my exhaust on
 

CanadaStang

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#10
  • Nov 13, 2004
  • #10
RysRed96GT said:
i'll do it tommorrow after i put my exhaust on
Click to expand...
Whoo Hooo!!!
Say,whatcha doing with your exhaust?
 

97GTSTANG

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Nov 13, 2004
#11
  • Nov 13, 2004
  • #11
What will the two step colder plug help with if you are not running nitrous? Will the two step colder make the engine run differently?
 

tomustang

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#12
  • Nov 13, 2004
  • #12
CanadaStang said:
Yup!! I think thats what you should do. Yup, most definitly. And then, eh hmm, if it's no trouble, could ya let me know how she runs.
Click to expand...


just do it!!!!!!!

no seriously, it's worth it, after i had mine done, well after the entire headswap i can easly light up the tires and im in an auto. but after the gap... bigger improvment
 

CanadaStang

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#13
  • Nov 14, 2004
  • #13
tomustang said:
just do it!!!!!!!

no seriously, it's worth it, after i had mine done, well after the entire headswap i can easly light up the tires and im in an auto. but after the gap... bigger improvment
Click to expand...
Thats good to know, I really like free HP Rats, I wish it wasn't so friggen cold here or I'd head to the track tonorrow and do some testing.
 

97GTSTANG

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Nov 14, 2004
#14
  • Nov 14, 2004
  • #14
What did you gap the plugs at after the headswap, and what plugs are you using?

tomustang said:
just do it!!!!!!!

no seriously, it's worth it, after i had mine done, well after the entire headswap i can easly light up the tires and im in an auto. but after the gap... bigger improvment
Click to expand...
 

tomustang

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#15
  • Nov 14, 2004
  • #15
97GTSTANG said:
What did you gap the plugs at after the headswap, and what plugs are you using?
Click to expand...


.40 and whatever parkway ford gave me with the PI kit
 

CanadaStang

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#16
  • Nov 14, 2004
  • #16
tomustang said:
.40 and whatever parkway ford gave me with the PI kit
Click to expand...
That would be Motorcraft AGSF 32PM
Have you ever had any issues with pre detonation after the headswap tomustang?
 

RysRed96GT

I like it FURRY!!!
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#17
  • Nov 14, 2004
  • #17
my car detonates slightly as it is now. platinum plugs gapped at .054 . maybe this would help me out some.
 

tomustang

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#18
  • Nov 14, 2004
  • #18
the car runs smooth, but i haven't had any tests, tunes, or dynos so i don't really know
 

CanadaStang

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#19
  • Nov 14, 2004
  • #19
RysRed96GT said:
my car detonates slightly as it is now. platinum plugs gapped at .054 . maybe this would help me out some.
Click to expand...
Are you going to switch to the coppers or just regap the platinums?
 

RysRed96GT

I like it FURRY!!!
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Apr 9, 2001
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Pasadena, MD
Nov 14, 2004
#20
  • Nov 14, 2004
  • #20
CanadaStang said:
Are you going to switch to the coppers or just regap the platinums?
Click to expand...
i'm gonna try coppers
 
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