Quote:

There are some 440 Cast pistons(cheap) with approx. 1.912 Compression height. A 440 with .040 overbore = .018 overbore in a 400. The only thing that might be an issue is the weight. That'd be .022 below deck and as a flat top (no reliefs)would make about 8.99:1 Comp. Just some more food for thought.

I did this very thing a dozen years ago. I used a .060 over 440 piston. I believe it was a 72-78 replacement piston. I don't know the weight difference but I didn't rebalance (I know I should have)and it hasn't shaken itself apart yet and it's pretty much my daily driver.