Best Budget Build Motor

I didn't say a stock magnum 360, but a magnum 360 with stock heads. The MP360/380 makes over 400hp which so can a higher built 318 but the 318 will make less power overall under the curve and probably 50 less foot pounds of torque. Sort of important in a truck. Plus he says he has access to a mag360 so it is using what he has. He doesn't have a set of ported mag eq heads so how is that more cost effective?
318 can be OK but a 360 will always be better part for part, if he were going to invest in heads they would be even more effective on the 360 rather then trying to prove something with the 318.