Trying to read 440 stamp

[wedged]

The stamp on my motor was a poor strike. What I see is G440+X (where the "+" is a Maltese cross)
I take this to mean "1971 440 with .010" undersized crankshaft"

Does that look correct? I know the the motor isn't correct for the car as it originally had a 383.

 

[69Bee]

Yes, a 0.010" US crankshaft. You then need to look at a crank counterweight for a M-10 and/or R-10 to determine if either or both came that way.

 

[wedged]

Thank you 69bee. Is the .010 under crank considered inferior and worth reusing? I'm about to rebuild the motor and if the crank needs a regrind, i wonder if thats too much

 

[69Bee]

There is nothing wrong with an undersized crank. No different than having any other crank ground today. As long as the radius is done properly, a crank can be ground way past what available bearing size exists. An RB crank was ground 0.125" on the mains to fit a B motor for a poor mans stroker. There is even a Ford combo where the crank is ground 0.280" to fit another block. Rod journals are offset ground, and ground smaller for different rod combos all the time. Done correctly (radius grind and finish), you do not loose crank strength by having it ground. The only caveat to that would be cranks with "splayed" rod journals. Back to your crank, have it ground 0.020/0.020 and don't worry about it. It will be straight, round, and indexed.