Does anyone know what the correct compression should be on x351 5.0 na engines?

 

Yep, 11.5 : 1 for the NA (9.5 : 1 for the SC).

 

So sorry for not being clear about my enquiry......
I was looking for the compression pressure one might expect from a gauge reading, thanks !

 

The manual is not real specific and does NOT give any numbers!

First they shown this diagram for you to write down each cylinders readings.
Two boxes for each cylinder. You should be doing a dry test first then add a small amount of oil (10 ml) to each cylinder and repeat the test for the wet results.




But to interpret the results the manual states.




So no set number and the readings are a relative measure I guess?

Sorry not much help?
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