According to Seat Guru, the economy seat pitch in the current “normal” 162/12 configuration is 31-33” for the 738 and 31-34” for the 7M8. It doesn’t say where the demarcation between 31” and 33 or 34” is.

The pitch in the exit rows is 35 or 36” from my memory. Again, be aware that in the forward exit row 13 and in row 12 the seats don’t recline.