Whats better and why?

Which one works better with factory wires?

Of the copper (bosch, NGK, champion, ...) which ones seem to work the best?

 

I personally like the Champion copper plugs (I'm old-school) but you'll have to change 'em more often. Other than being long-lasting, I'm not sure exactly what the iridium plug's claim-to-fame is.

 

copper i think is a better conductor. iridium just last longer

 

Ditto. I run NGK TR-55 regular copper and change them every 30K or so. Seems to idle a little more smoothly compared to stock plat plugs.

 

whats the part number for the NGK tr55? Assuming thats the proper plug for a stock engine, no FI/Nitrous. I tell my guy that I want some NGK TR55s, and he looks at me crazy. is there another part#?

 

Iridium plugs last longer and have a better burning spark kernel. If you run LT headers or have alot of fuel....you need to run Iridiums.

 

What is a "Spark Kernel"?
Would that increase burn efficiency and mileage?

 

Iridiums will definitely last longer, and supposedly burn off more carbon (according to Denso...). My truck came with platinums from the factory, then I ran iridiums for a while, and am now using NGK TR55 copper plugs. I honestly haven't felt a difference or noticed any mpg change between the 3, and they all seem to burn the same when looking at the plug. So it's basically your call...if you want to install plugs and not have to worry about changing them for anywhere from 60-90K, go with iridium. If you plan on modding alot and don't mind swapping out plugs every 20-30k, get the coppers. Iridiums can cost anywhere from $6sih to $11-12 a plug, while the NGK TR55's are less than $2 a plug.

 

Just out of curiousity, was that before or after you put on the LTs?

 

It was before, when I had the shorties