I am aware there are 2 sizes of crankshaft pilot bores. Either 1.550 or 1.813. I bought a long block and the crankshaft bore at the end is 1.780!!! I'm stuck - What do I have? Can I machine my torque convertor hub to fit my crank or will that cause problems?

Actually, I believe the two torque converter nose diameters and crank counterbores are (nominally) 1.5" and 1.75", so your long block would have the larger, 1968-up counterbore. If you're trying to use your new engine in front of a 1967 or earlier automatic, you can get the necessary adaptor ring from Pat Blais, tflitepatty@verizon.net .

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