340 vs 360 on a full out race engine build both taking out to there max rpms the 340 would have a advantage over 360 with its bigger bore (better breathing) and shorter stoke (higher rpm capability).
340 powerband will be 300-500 rpms higher than a similar 360 which would make the 340 needed more stall and gear to give same performance as a 360. And yes a similar prepared 360 will make more torque then a 340 but that only matters if your racing dyno numbers with the right gearing both will put similar torque numbers to the ground. The main advantages a 360 has lower cost power will be lower in the powerband and requiring less gear and stall, all around just a little more streetable. Or use 340 block with a 3.58 crank and have best of both worlds.