If I am not mistaken, all of these trucks as the cobra now have platinum plugs standard for the "100,000" mile tune up.

When I had my cobra built up to over 700 hp, every mustang tuner i used still recommended a basic copper plug.

I have not heard much as to any lightning owners using a copper plug.

Anyone have experience with these.

I mean if i can run 18psi on a 10.5:1 compression with no spark problem on the cobra, why not 13 psi with much less compression on the L?

 

Terry, I have tested the Autolite 103s, which are your basic, no gimmick type plug, and I didn't like them. Idle was rougher, truck felt kinda sluggish, and no increase in performance. It could have just been a freak thing, but all the other kinds of plugs we use didn't do any of that.

 

That sure is interesting.Copper is one of the best electrical conductors available.Platinum isn't as good a conductor, but is a "harder" metal..hence its longitivity.I still think the NGK's are the best.

 

High conductivity copper (16% annealed) is Rockwell B 45.
High conductivity copper (35% annealed) is Rockwell B 47.
Electrical Resistivity 1.71E-06 ohm-cm at 20° C (68°F).

Hard drawn Platinum (50% cold worked) is Rockwell B 49.
Annealed Platinum is Rockwell B 40.
Electrical Resistivity 1.06E-05 ohm-cm.

Platinum is not a lot harder.
It is a lot more resistant to chemical attack...

 

NGK V-Power plugs (TR5, TR6, etc.) have Solid Copper Cores . .

http://www.ngksparkplugs.com/product...uvs/vpower.asp

 

Sal,

as I have almost 9 k on the truck, i was going to go ahead and have a buddy of mine help me with my plug change.

which plug would you recommend for me.

i plan on racing every other weekend i would say and i drive the car back and forth to work a total of 3 to 4 hundred miles a week?