crankshaft journals

[boilermaker27]

I have a 390 engine out of a 1966 Ford Thunderbird. The engine was rebuilt and there is a tag indicating the rod and mains were ground down to .020 under. I have the engine torn apart and plan to mic. the journals to see if they are still within specifications. Problem is can't find the specifications for a 390 crank that has been ground down .020. Anyone know the journal sizes so I can check it with a micrometer?

 

[HeadacheGuy]

I have the stock specs at work someplace, I will look tomorrow but if you have the standard spec just knock off the .020. The tolerances don't change. If you are close to the plastigage stage look for .001 to .0015 (the latter being a safer bet for all conditions) bearing in mind plastigage is a good guide but not totally acurate.