Spark Plug Heat Range 44

[jprevat]

I am trying to find the right Motorcraft spark plug for my 1989 2.9 so that I can advance the timing and get a little more power out of it. The problem is I have no idea where to find heat range 44 plugs. It seems like MC ranges only go from 0-10 so I am lost. If yall happen to have a part # somewhere I would really appreciate it.

 

[AndyB.]

Motorcraft original plug would be AWSF42C, heat range 44 would be AWSF44C. Personally, I’d buy these:

Genuine New Motorcraft AWSF42P Spark Plugs. https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/282794423258

 

[jprevat]

Thank you for getting an answer to me so quickly. Why would you go with those from your link rather than whats recommended in Kuntz Korner?

 

[RonD]

2.9l uses Motorcraft AWSF-42C

AWSF= 14mm tappered seat
4 = heat range
2 = tip design
c = copper electrode

So heat range is not 42 or 44 it is 4

Decoder here, worth a look: http://jimsprojectgarage.weebly.com/motorcraft-spark-plug-information.html

I doubt you will need to change heat range for spark timing change only

 

[jprevat]

Thank you very much. That definitely clears up a thing or two.