I went from ported 302's to mildly ported 587's around the same flow (240's) nothing else was changed and it was all top end and lost all the torque under the curve.
I remember Lead69 posting this:
"Very cool thread,nice to see you document this for everyone.I ported a set of 318 heads for a street 360 build with awesome results.I ended up raising the legnth of the roof to the stock 360 port size and reworking the short turn and opening up the bowl to 90% of the intake.Also did the same as you on the exhaust side,original 1.78/1.5 but they did have a serdi valve job.The heads went on a stock 360 shortblock with an actual 8.6 compression,ported performer intake (360 size runners/mild plenum work) 600 holley,cheap headers and an xe274 and was a screamer,upper 12's all daylong with 3.23s in a 70 dart!."
"IMO port the 318 heads,I would keep the valves stock and go 1.51 on the bowl and port match to these gaskets
http://store.summitracing.com/partdetail.asp?part=FPP-1243&autoview=sku with this and typical exhaust mods you can gain a ton of power while having a ton of low end and high velocity.I did this to a 360 (kind of an experiment) that wound up at a true 8.7 comp.,xe 274,port matched performer,1in. spacer and headers with stock rocker gear.This engine ran like an animal and made low end like a 383,it pulled cleanly to 6k and made a ton of power,with 3.23s and a 904/2,500 stall it easily ran high 12 cars so I have no doubt it was a 12.80-12.70 combo with 3.91s at the track."