thanks

how interchandeable are element cores. is the electrode platinum white stuff as good as copper ?

Platinum is less subject to electrode wear but isn't a real good heat conductor so they run hotter, stay cleaner, but can become a pre ignition source especially with older chambers where swirl isn't highly present. In high swirl chambers the plugs get a lot of cooling by mixture being directed over the electrode.

Copper is softer which is given to faster electrode wear, but is a very good conductor of heat and electricity. These run cooler which while reducing the chances of them causing pre ignition also increases the tendancy to foul making them sensitve heat range, mixture ratio, and low engine opertaing temperatures, short drives, etc. Aluminum heads accentuate these problems with copper plugs
by running them too cold since the aluminum is heat sinking the plugs. To some extent with aluminum heads you can fix this by running the coolant thermostat 10 to 20 degrees hotter. As with platinum plugs, modern high swirl chambers while washing the electrodes clean also cool them, perhaps too much.

Bogie

 

If you have fouling issues, your plugs are either too cold for the application or you need a better tune up in your stuff.

I used the Accel shorty plugs for years both on the street and in racing applications. They are a good plug. I'd run them now if they offered one that meets what I need but they don't. So I run NGK when tuning and Autolite racing plugs once tuned, they tend to last a little longer than NGK.


Yes, the AR series Autolite plugs are fine in a street application. They don't have an internal resistor like a standard plug does, but as long as you have quality suppression wires it's not an issue.

Here's a copy of an interchange chart for those wondering minds:

 

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Here's a copy of an interchange chart for those wondering minds:

Great chart and thank you for sharing. It will be very usable I'm sure.

 

Champion uses a completely different heat range scale/plug numbering system than Autolite or NGK, that is why is looks so different. That is also why you need to use a heat range/crossover interchange chart to compare plugs. You can't compare them directly just using the numbers on the plug.

AC Delco also uses a different chart than either that has already been mentioned.

 

There's why. Thank you.

 

I started using Denso spark plugs five years ago. They are made in Japan and are top quality. That was after I found out AC Delco parts were made offshore by the lowest bidder. GM sold the AC Delco parts division and the last AC Delco plant in the US closed in 1996.

It is now ACDelco with no space between C and D.

Champion made the first projected tip spark plugs. They were designed by Smokey Yunick for his Pontiac race cars.

 

Personally, I wouldn't run champion in anything, including my trimmer and lawn mower....I actually run ND or NGK in those.....

My dragster gets what I already mentioned, NGK most of the time and when tuning, Autolites once tuned and if I'm not going to be making any changes to that tune since they last a little longer.

If you look at the plugs available today, there's a bunch, and a lot of misconception on them. From my experience, I'll give you my personal list of what I believe to the best plugs. Not all will have part numbers for certain applications, but most will be covered.

NGK, Nippondenso, Bosch, Autolite, Accel, MSD, AC Delco

Possibly the worst plugs you can run:

Champion, Mighty, E3 and any other gimmick plug.

Best plug available but is also one of the most expensive:

Brisk, several different electrode designs depending on application.

For racing applications, standard electrode design is best in 99% of the applications. Fine wire and exotic metal tipped plugs have no place in a racing engine but are generally ideal for most OEM applications.

I'll say it again, this is in my experience. It may differ with yours, doesn't make it right or wrong, just my experience....