Is it normal for plugs 1 - 3 to look hardly used, but plugs 4 - 6 the tips are much more eroded @ 57K?

Does this indicate something abnormal?

 

From the factory, they come with different plugs on each bank. Is this the 1st time you've changed the plugs??? If so, it is normal.

 

First time yes. Thanks for the info.

 

Do you know why or the reason behind why they use different plugs on each bank? I don't so was wondering if someone else could tell me, thanks.

 

Did not know that about the plug's being diff.... strange.

I changed mine for the first time at 65k and i found that one of them was broken (the tip was broke off in the plug wire boot).

 

It's so they can save some money, on one side, there is platinum on the electrode only, on the other plugs, the platinum is on the tip only. That way they don't have to use more expensive all platinum plugs. For some reason on one bank of cylinders the coil runs backwards and the spark runs the other way, I found this out messing with the ignition system of a 96 Cougar with a 3.8 in it.

 

I am attempting to install an mobile amateur radio (HF) system in my 4.2. I'm getting large amounts of electronic noise from the distributor ( what's the proper name please) and wires. Any one have suggestions how to shield it . Are there special plugs that would help ?

 

Resistor plugs?

 

It has to do with what they call "waste sprak". The coil fires a reduced amount of spark on the cylinder that's Not firing.
It is true that the direction of the spark is different on the two banks of cylinders so Ford decided to save some money by putting the different plugs in.