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do plat plugs = power loss

  • Thread starter Thread starter Iwant5.0
  • Start date Start date Jul 28, 2003
I

Iwant5.0

New Member
Jan 9, 2003
89
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NC
Jul 28, 2003
#1
  • Jul 28, 2003
  • #1
I made the mistake of using bosch platium plugs and now my car feels like it has lost a little pep. Should i replace them with motorcraft ones if i want that pep back? The car just isnt pulling like it was before i changed them and how often should a ignition coil be replaced?


thx
 

BelueLX

Founding Member
Jul 10, 1999
1,195
1
0
Jul 28, 2003
#2
  • Jul 28, 2003
  • #2
maybe you left some of them unhooked. j/k. ive noticed no power gain using platinum plugs but i didnt notice a power loss either. id only use them if you have an engine where the plugs are a PITA to get to (Mitsu V-6, LT1, etc...) because they are supposed to last a long time.
 

JSSuper455

Founding Member
Aug 1, 2002
197
0
16
UT
Jul 28, 2003
#3
  • Jul 28, 2003
  • #3
I had Bosch Plats installed in my car when I purchased it. They were very new and the car had just had a complete tune 1 month before I purchased the car so I didn't bother changing them for a while. I have since done a re-tune and replaced those plugs with copper core Autolites because the engine would sputter and pop and miss at 3950+ rpms. Now that I have the Autolites in I can definitely say that the car has slightly more kick to 4k rpm, and continues to pull hard right up to redline. I was amazed that a sparkplug could be such a big problem, but I am not the only one on here that has had a similar problem with the Bosch Plats....... Go back to Autolites, Motorcraft, or Champion copper plugs.

My .02
 
M

matm347

Founding Member
Aug 29, 2000
2,056
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0
Jul 28, 2003
#4
  • Jul 28, 2003
  • #4
The Bosch plats electrode causes more quench due to their design.
I have heard great things about the new iridium plugs, NGK and Denso offer some performance plugs that have seen ~10hp gains due to the very thin(.4-.7mm) fine wire core. I am running NGKr's right now, but plan on swapping to iridium soon, they say they are OK for N2O as well where platinum plugs are not.
 
N

NACOUPE

New Member
Jul 25, 2003
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0
WEST VIRGINIA
Jul 29, 2003
#5
  • Jul 29, 2003
  • #5
yeah it seems nowadays the bosch just don't work well in fords. i took 2 sets back cause the same thing. my friend had the same thing happen to his Ranger. mine choked bad with the air on pulling a hill or speeding up.
 

Warbird19

Founding Member
Sep 27, 2001
742
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16
Washington, Federal Way
Jul 29, 2003
#6
  • Jul 29, 2003
  • #6
From what i heard plat. plugs make a smaller spark, and thats not helping at high rpms. Ive heard people say that the spark gets blown out.
 

whitemustang89

Member
Dec 15, 2003
166
0
17
in the sticks of arkansas
Dec 17, 2003
#7
  • Dec 17, 2003
  • #7
i have always had trouble with plats if i was u i would just stick with the motorcrafts thats what i have and the car pulls great. every gear every rpm


----89lx bbk fenderwell intake bbk headers,mac offroad h pipe msd ingnition and coil hurst short throw and the old school 7 inch 10 hole rims.----
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,217
17,899
224
Massachusetts
Dec 17, 2003
#8
  • Dec 17, 2003
  • #8
Platnium isn't as good a conduction of electricity as copper is.

As my expeirence goes, no platnium plug works well in the 5.0 motor.

Our motors live on Motorcraft or Autolite copper plugs. Just runa simple Autolite 25 and call it a day
 
S

somersdp

New Member
Nov 16, 2003
191
1
0
WPB,Florida
Dec 17, 2003
#9
  • Dec 17, 2003
  • #9
I have bosch plats in my stang, well now Im gonna change them out after reading this thread. Do you have a part#> Or will the Autolites 3924's work fine with iron heads?
 
9

91conv.

Founding Member
Oct 14, 2002
149
0
16
Nebraska
Dec 17, 2003
#10
  • Dec 17, 2003
  • #10
I believe since mid 90's that most auto makers put platnium plugs in at the factory. I know ford did.
 
8

89tang

Founding Member
Oct 20, 2000
2,508
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0
Newark ohio
Dec 17, 2003
#11
  • Dec 17, 2003
  • #11
somersdp said:
I have bosch plats in my stang, well now Im gonna change them out after reading this thread. Do you have a part#> Or will the Autolites 3924's work fine with iron heads?
Click to expand...

Yeah the autolites work fine just use the stock replacement 25's
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,217
17,899
224
Massachusetts
Dec 17, 2003
#12
  • Dec 17, 2003
  • #12
91conv. said:
I believe since mid 90's that most auto makers put platnium plugs in at the factory. I know ford did.
Click to expand...

Not on the 5.0 though. It's ignition was engineered with copper plugs in mind.

Ford put platnium plugs on my Lincoln. They also claim they are good for 100K miles. It says right in the manual that my plugs didn't need to be changed til 100,000 miles.

Plat plugs were basically a marketing ploy. Think about it..less maintainence equals saved money so people bought into that. Ford could care less that they lost a bit of power on the engines. It's all about the bling bling.

Only benefit of plat plugs....longer time intervals between changes. THAT'S IT
 

tvmango

New Member
Oct 27, 2003
667
0
0
bradenton florida
Dec 17, 2003
#13
  • Dec 17, 2003
  • #13
Platinum plugs were made for one thing- longer lasting - not for performance, or any other reason, plat's are great for commuter cars not high horsepower vehicles. And don't get fooled by bu--sh-t splitfires and all the other plugs to give you power, like the guys above said go with the original copper style plugs, and there less than 2 bucs each...
 
S

somersdp

New Member
Nov 16, 2003
191
1
0
WPB,Florida
Dec 17, 2003
#14
  • Dec 17, 2003
  • #14
Im sold!!!!25's it is!!!
 

cleanLX

Founding Member
Jan 17, 2001
976
537
144
Dec 19, 2003
#15
  • Dec 19, 2003
  • #15
I ran 13.00's with bosch platniums on a totally stock long block, stock electronics, full weight stock suspensioned car that is in the sig., that is in crappy 2600+ d/a conditions.
Car would pull to 5600 1st gear shift point with ease.

I'm now running NGK's 'cause I got them free. I saw no driveability or performce benifits when I switched to NGK's.

I actually had better 60' times with the Bosch plugs in the car, not that I would attribite it to the plugs.
 

maverick0716

Founding Member
Jan 12, 2002
3,924
0
56
Chilliwack, BC, Canada
Dec 19, 2003
#16
  • Dec 19, 2003
  • #16
Quick question......What about for aftermarket hi-po aluminum heads? Would Autolite 25's still be best? Or if not, what would?
 
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