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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

I've Been A Bad Boy...

  • Thread starter Thread starter joshjwc9
  • Start date Start date May 31, 2012

joshjwc9

Active Member
Jun 12, 2006
1,095
17
39
Palm Harbor, FL
May 31, 2012
#1
  • May 31, 2012
  • #1
I've neglected to change the plugs on my Stang here. I've been supercharged and have gone more than 12k miles on the copper Autolite 103's that are in it. Seeing maybe 16.5 mpg city and only 21 on the highway. Car still runs good, but it will run better with different plugs, I'm very sure of that.

I'm tempted to just go get 8 more 103's, but want to know if switching the the Motorcraft sp505's are any different, or if the difference between the half thread design old Motorcrafts and new full thread design will throw anything off detonation wise.

Someone better give me what I got coming my way.. (all women come to the front of the line please..)
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
May 31, 2012
#2
  • May 31, 2012
  • #2
If it's not misfiring now changing plugs won't likely change much but it's probably a good idea to swap 'em anyway. Just make sure you get the correct heat range.
 
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