Gas in through carburetor

[kaiserfrazerlibrary]

Your chart is new and reflects Champion's post 1963 re-identification;  My info goes back to late 1940's.  My 1989 Weatherley book for AC plugs shows same as your Champion chart. 

You are also correct about the less likely to foul part; the Service Bulletin that advised the running change from A-5 to A-7 in 1951 Kaisers mentions less likely to foul than the A-5 as a reason for the change as well as better burning of fuel/air mixture.

[Logan]

So, clear this up for me.  Which is hotter, J8 or J9?

[kaiserfrazerlibrary]

Let me post the chart from my Auto-Lite book when I get home tonight.  It also shows AC as well as A-L and Champion for reference purposes. 

[Logan]

Thanks.

[kaiserfrazerlibrary]

I could not find the Auto-Lite Want Book (which has a chart set up like a thermometer going lowest to highest ranges) but I did find this chart and other reference material  from Auto-Lite's 1957 issue spark plug guide/catalog.  Also listed is the puzzling thing that is from the 1949 Kaiser Salesman Facts Book, Specification section.  It shows the AC 45 and Champion J9 or Autolite A5 plugs used in the 1949 Kaiser engines. 

I do notice that the 1957 A-L chart shows an J-9 with higher heat range than the J-8, which Auto Lite matches with the A-7 hotter plug.

While some books state the difference between A-5 and A-7 is heat retention more than higher temperature spark, I did notice that when I switched plugs from J-8 to A-5 in the Business Coupe and the 1952 Kaiser later deLuxe, the temperature gauge indicated the engine was running a bit cooler with the A-5.

[Logan]

Thanks for posting these.

[kaiserfrazerlibrary]

Over the weekend I found the Auto-Lite Want Book that had the other heat range chart in it.  The chart is c.1941 (based on cover and Auto-lite vehicle applications (crosley but no Graham and no postwar stuff).  This chart does show the lower the Champion number the higher the heat range.   Go figure

[LittlePegasus]

While some books state the difference between A-5 and A-7 is heat retention more than higher temperature spark, I did notice that when I switched plugs from J-8 to A-5 in the Business Coupe and the 1952 Kaiser later deLuxe, the temperature gauge indicated the engine was running a bit cooler with the A-5.

What currently available plug is equivalent to the Auto Lite A-5?

[vt2000driver]

autolite a5 are avalable on ebay now


www.ebay.com%2Fitm%2FA5-000-12405-J-Spark-Plugs-9x-NINE-9-NOS-Autolite-See-pictures-Vintage-%2F200955384483%3Froken%3DPWA4Xr#

[retired wrench]

 Realto is right on champion plugs a higher number is a hotter plug.

[retired wrench]

  One more time,,,,,,what determines the heat range of a plug is the distance from the tip of the center electrode to the point that the porcelin {sp} contacts the metal body of the plug. The longer distance the slower the heat dissipates making it a "hotter plug"  The heat range of a plug has NOTHING to do with the intensity of the spark. This is a function of the ign system. Now if you have an oil burner that oil fouls plugs and you put a hotter plug in that burns off the fouling it will run better,,not because the spark is hotter because the plug is cleaner. Too hot of a plug will melt a hole thru your pistons,too cold will foul and waste fuel. And I didnt get this stuff from a book it comes from 54 years of playing with this stuff.