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Quick Spark Plug Question

  • Thread starter Thread starter bgrd351
  • Start date Start date Nov 19, 2006

bgrd351

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Jun 10, 2005
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Jacksonville, Fl
Nov 19, 2006
#1
  • Nov 19, 2006
  • #1
I decided to swap out my plugs to some NGK tr5's (crossed over from agsf22c motorcrafts) for the one step colder to help against tip in rattle and was wondering what gap I should set them to. So any one running the colder plugs on a N/A setup, what did you set the gap to?

Also, I got a set of Autolite 103's as a back up...which would you use and why?
 
K

Kilgore Trout

Fried or Broiled ?
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Mar 30, 2005
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Nov 19, 2006
#2
  • Nov 19, 2006
  • #2
I would use Motorcraft AGSF-32C gapped at .054 since you do not have nitrous or s/c you should to IMHO.

So you went to the parts store and bought two complete sets of plugs? NGK and Autolite?
 

bgrd351

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Jacksonville, Fl
Nov 19, 2006
#3
  • Nov 19, 2006
  • #3
Kilgore Trout said:
I would use Motorcraft AGSF-32C gapped at .054 since you do not have nitrous or s/c you should to IMHO.

So you went to the parts store and bought two complete sets of plugs? NGK and Autolite?
Click to expand...

I have been working with Justin@VMP and he suggests running the AGSF-22C's but I went to my local Ford dealer and they said they only carry/stock/look up the stock AGSF-32PM's which is what I have in my car and have a bit of rough tip in/rev to about 2k. He said to use 22's and I have done the search on here and found several tuners on here seem to favor one heat range colder copper plugs for the PI cars.

And yes, I bought one set (NGK) yesterday while searching local parts stores before they closed and when I went to verify that the NGK TR5's were for my car and one heat range colder I found they equal BOTH the 32's and 22's depending what source you check. So I bought the 103's that I know for sure are colder but dont have the V groove that I use to like to use on my old 5.0 (accel U grooves)

So I am going to install the NGK's in the morning before work and was hoping to find out what the recommended gap is for the colder plug because I have seen from .035 to .054.
 
K

Kilgore Trout

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Nov 20, 2006
#4
  • Nov 20, 2006
  • #4
Well, the rearmost two cylinders run hot so it does not hurt to run a colder plug to combat this problem. The real fix is to do the cooling mod though... I think you should be ok at .054 gap.
 

BooWFO

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Nov 20, 2006
#5
  • Nov 20, 2006
  • #5
tr6's are NGK's one heat range colder. the 5's should be stock heat range.
I've ran the tr6's put about 20k miles on them. I have switched to the autolite 103's and haven't noticed a difference.
I found on my car opening the gap up a tad helped out NA performance and fuel economy. My car likes. .040 gap on a 1 heat range colder plug.
Now if the NGK tr-6's were as easy to pick up as the autolites I would prefer them just because I have had such good luck, but the idiots that work at the parts stores drive me up a wall and I'm not paying 2 or 3 times to have them shipped in.
 

bgrd351

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Jacksonville, Fl
Nov 20, 2006
#6
  • Nov 20, 2006
  • #6
yeah...I want to do the cooling mod but I have to wait until I get a set of P&P heads and cams.
 

speedfreak98r

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Jan 31, 2006
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Nov 20, 2006
#7
  • Nov 20, 2006
  • #7
bgrd351 said:
yeah...I want to do the cooling mod but I have to wait until I get a set of P&P heads and cams.
Click to expand...
Cooling mod?
 

bgrd351

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Jun 10, 2005
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Jacksonville, Fl
Nov 20, 2006
#8
  • Nov 20, 2006
  • #8
BooWFO said:
tr6's are NGK's one heat range colder. the 5's should be stock heat range.
Click to expand...

interesting...this is why my head was swimming trying to find out what plugs were right. I even went into NAPA here and they made the cross ref. for me from the AGSF-22c's to NGK and it came up TR5's (2238). And I found the same thing on different sites where the TR5 and TR6's are both equal to colder plugs but only the TR6 were not equal to the stock heat range.

So, I didnt get up in time this morning to put in the TR5's so I think I will put in the 103's then tonight. I would perfer the NGK but I will have to call around to see is anyone has the TR6's.

And thanks for the info on the gap...I was guessing about .045 since it was between what I heard for a range.
 

bgrd351

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Jacksonville, Fl
Nov 21, 2006
#9
  • Nov 21, 2006
  • #9
quick update:

I installed the 103's gapped at .045 this morning and the car ran smooth and seemed to like the new plugs.

things to note: I was throwing p0172, p0175 before the plug change and was running the AGSF-32PM's. I also have the SCT PRP w/Xcal2 and was fighting my car to tune down low.

After driving a bit: I datalogged to check my tune --almost dead on now (stft) and I got on it once today from a 5 mph roll and spun the new 315 Sumo's all the way thru 1st and half way thru 2nd until I let off which I could not do before the plugs. I feel it is half my tune being right and half the fact my car "liked" the colder plugs.
 
K

Kilgore Trout

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Nov 21, 2006
#10
  • Nov 21, 2006
  • #10
How did the old plugs look?
 

bgrd351

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Jun 10, 2005
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Jacksonville, Fl
Nov 21, 2006
#11
  • Nov 21, 2006
  • #11
a little black on the center electrode but the white part was a little grey I think. I can post a pic of all 8 when I get home. But they were not clean and I know my tune was off. It just seemed that I could lean it out enough that the trims would be almost spot on and then I would get tip in rattle and a little rattle under WOT. Alos I had that annoying pop/miss at idle up to 2k and that seems to be gone with the colder plugs. (pop/miss has been there thru 764's and 32PM's and different tunes)
 
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