Spark plug question

Fast89GWILL said:

Pulled awsf42ca out of my 89 fox and the OEs are won't fit because of the diameter of the plug above the threads.

I bought the car as is and here these are used in GT40S. No clue what the prior owner may have done. All plugs the same.

Any ideas or thoughts and similar situations?

Thanks!

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Fast89GWILL said:

Pulled awsf42ca out of my 89 fox and the OEs are won't fit because of the diameter of the plug above the threads.

I bought the car as is and here these are used in GT40S. No clue what the prior owner may have done. All plugs the same.

Any ideas or thoughts and similar situations?

Thanks!

Click to expand...

Fast89GWILL said:

Pulled awsf42ca out of my 89 fox and the OEs are won't fit because of the diameter of the plug above the threads.

I bought the car as is and here these are used in GT40S. No clue what the prior owner may have done. All plugs the same.

Any ideas or thoughts and similar situations?

Thanks!

Click to expand...

93gtmustang said:

I just bought some plugs for my GT40-X303 heads.
The recommended plug for my heads in Motorcraft is AGSF32C. (SP-447-X, SP447, AGSF-32-X)
Autolite plug would be #104

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