[chiphead]

I see a few flaws with this approach to selecting pistons.

Finished bore. Do you know exactly what your finished bore is? How are you setting bore clearance? Auto tech can set the skirt clearance if you know the finished bore down to .001

Deck height. Don't order pistons without knowing deck. Otherwise you'll have to deck the block a bunch afterwards. Auto tech lets you set the pin height if you know the number to use.

Chamber size. Do you even know the finished chamber size of your 670s? Never order pistons without knowing finished chamber. Any head work is going to change the chamber size.

Future growth. With a big piston dish, how are you going to raise compression if you swap to aluminum heads?

What ring pack? Metric or 1/16?

What ring pack placement? How deep are the cyl reliefs? Don't hang a ring on the scallops!

Not trying to be difficult, but you can paint yourself into a nasty corner with piston selection.