David Vizard bench flows a BBD 2bbl

Ted265 said

There's no way you will even get close to a 3.58" stroke by offset grinding a 318 crank.

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If he offset grinds it to small journal SBC size, he could gain about 0.13 which would put the stroke about half way between a 318 and a 360. Hopefully he's just adding a little to get the pistons to the top of the bore as others have suggested.