I recently did this very thing went from 360 to 418.
swapped headers, cam, intake, carb, convertor, trans, etc over from 360 to 418
only difference was the 418 had more compression.
went from 11.26 to 10.77 ET. Half a second is a lot.
that is a whole bunch more than 34 horsepower.
I talked to Ken Hensley years ago about this( owner of Hensley performance, well known Mopar engine shop), and he said, all things being the same, he sees 3 to 4 tenths in ET going to the stroker. I have found that to be true in several combinations.
I suspect my 5 tenths in this case was the extra compression.