This maybe a crazy question, but here’ goes: Will a rotating assembly kit for a 440 cu engine fit into a 400 and if so with what modification. I have all components from a 440 that was bored 0.030. Now, if this does not work then I may have to find a 440 block.
There’s two facets to this:
> The 440 (RB, also 413 and 426 CID) has larger main bearings, and, therefore, larger main bearing bores in the block than B engines (350/361/383/400). To use a 440 crank in a 400 the block must be align bored to the 440 side. Some folks cut the crankshaft journals to 400 size, but that weakens it significantly.
> The RB has a taller deck height than a B. Therefor, you need some combination of shorter con rods and/or “hockey puck” pistons.
The 440 was in a bazillion cars from 1966 thru 1978; the 400 was 1972 thru 1978.