Budget cylinder heads for a 318
"325hp out of a 318 ain't no small thing", means;
it costs money.
325 hp 318 stock heads = 9:1 xe268h 4bbl headers
325 hp 360 stock heads = 9:1 xe256h 4bbl headers
Where the extra expense ?? beside 360 would have slightly cheaper pistons
Give them both the same heads and 318 would need less cam probably the same cam as the 360.
The OP still hasn't shown any desire to build a 360 why push it ??
would a 360 make slightly more power in a streetable powerband like idle-5200 rpm = yes
if built to make the same power would the 360 be slightly more streetable since = yes
will the 360 need less stall and gear = yes
at 325 hp does it matter all that much = no
if the OP is ok with this why can't you be ???