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Sparkplug differences!?!?

  • Thread starter Thread starter Vapors
  • Start date Start date Sep 8, 2005

Vapors

New Member
Aug 26, 2005
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Bakersfield
Sep 8, 2005
#1
  • Sep 8, 2005
  • #1
I have an 87 lx with a 302 and I just bought some bosch super sparkplugs. I pulled the old ones off, and they are bosch platinums, and the thread length on the platinums is about 1/4 inch longer than the supers. I specifically asked for plugs for an 87 with a 302. I also have GT-40 heads btw.

There are numbers on the part right above the threads on both plugs, the #s on the platinums are HR9DPY, and the #s on the supers are HR10BCY.

Are the supers going to be ok to run?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 9, 2005
#2
  • Sep 9, 2005
  • #2
So they gave you plugs for E7 heads, even though you have Gt40 heads? I would ask for plugs for whatever year of explorer (etc) that those heads came from (so you have the right plugs for the heads, not the right plugs for the 'car').

Good luck.
 
F

fiveohh94gt

New Member
Dec 26, 2003
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0
Sep 9, 2005
#3
  • Sep 9, 2005
  • #3
gt40 heads take a different plug than the stock heads, i believe its an autolite 764 or equivalent
 

Vapors

New Member
Aug 26, 2005
39
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0
Bakersfield
Sep 9, 2005
#4
  • Sep 9, 2005
  • #4
If I just took them back and got the platinums, it should be fine right? Even though the platinum part #s are the ones that come on the "car" Its been running fine with the platinums...
 
F

fiveohh94gt

New Member
Dec 26, 2003
277
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0
Sep 9, 2005
#5
  • Sep 9, 2005
  • #5
get the part store to cross the HR9DPY plug and give you the same one, or get one for an explorer with the 5.0 or like a 94-95 cobra
 

srothfuss

Last night I stabbed the same guy 7 times in a row
Oct 17, 2004
1,796
3
0
Woodward Ave.
Sep 9, 2005
#6
  • Sep 9, 2005
  • #6
Your motor will run a lot nicer if you get some copper plugs... Definently take one of the old plugs back to the store and get a cross referenced plug that is copper instead of platinum.
 

Vapors

New Member
Aug 26, 2005
39
0
0
Bakersfield
Sep 9, 2005
#7
  • Sep 9, 2005
  • #7
What I dont get is that if the plugs that are in their(platinums) are the ones that are supposed to be on the car, why are they different than the supers that are supposed to be on the car?

Either way, I'll just take a plug their and get me one similiar. Copper is the better to go with than platinum?
 
P

PlumCrazy5.0

New Member
Apr 15, 2004
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0
northern new jersey
Sep 9, 2005
#8
  • Sep 9, 2005
  • #8
the gt40 heads are not your stock heads, they came stock on explorer 5.0s. tehy take different plugs than your stock mustang heads. this is why the numbers and the parts do not match up. take the old plugs with u to cross reference them to the ones u want.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 9, 2005
#9
  • Sep 9, 2005
  • #9
I would not even take the old plugs with me - you have no idea what the previous owner was doing. Plats are not nearly as good for performance as (annealed) copper, so that says something right there. Just search on here for the right plugs (there are different flavors of GT40 heads so I wont comment further).

good luck.
 
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