Spark Plugs C-4 Take Apart With Green # and letters
 

I have a NOS set of Four and would like to know what they fit and when the Green color was used..Have not seen many that way..

Re: Spark Plugs C-4 Take Apart With Green # and letters
 

Champion C-4 plugs were the replacement for the original 3-X plugs and for the Model-B. They were made over many years and in many iterations: black take-apart, non-take-apart, zinc coated, etc. I have some marked "Made in Canada".

Re: Spark Plugs C-4 Take Apart With Green # and letters
 

Actually Model B’s used the 3X. C-4’s were for the early V-8’s.

Re: Spark Plugs C-4 Take Apart With Green # and letters
 

John Stone is right on. the C-4`s can be used in the A`s an B`s but they are not correct for them. they do NOT go deep enough into the head. the 3X is the correct plug.
that is all I will run in my A`s.

Re: Spark Plugs C-4 Take Apart With Green # and letters
 

In 1932 Ford introduced a V8 engine and the C-4 spark plug was the official spark plug made for that engine and recommended by Ford.. The 3X was the official Ford Motor Company spark plug for both the Model A and Model B.

In 1933 the Ford V8 engine for that year and subsequent years did not use the C-4 and they would not fit.

Now suppose you operate a spark plug company who had thought Ford V8 would use the C 4 for a long time, and had produced large quantities of C 4 to meet the supposed demand.

Very likely what happened is that those C 4 plugs in the warehouse will fit the Model A and the Model B, and while not Ford recommended plug the heat range on them is close enough for satisfactory service so advertise them for aftermarket use on the A and the B. This is my guess as to the reason they were promoted as the aftermarket replacement spark plug.

Re: Spark Plugs C-4 Take Apart With Green # and letters
 

I am interested if you want to get rid of them.

Re: Spark Plugs C-4 Take Apart With Green # and letters
 

I miss read the title and was thinking of Splitdorf which were green.