360 stroker how much HP is picked up if everything else stays the same?

Because I like maths I just worked out 2 different scenarios:
A. 4.04' bore, 3.31" stroke, assumed compression height of piston of 1.6"

B. 3.91" bore, 4" stroke, same piston height

The smaller bore stroker has 17% more moving surface area compared to the bigger bore short stroke.

If anyone wants to check my maths feel free as I may have made a mistake.

It's not really apples for apples as I'm using 340 specs vs 318 stroked to 390, but you wouldn't find a reversed scenario of 3.31" bore with a 4" stroke, so it is a real world comparison.
With a 3.91" bore and 3.58" stroke it came out at 4.8% more area subject to friction.