Worth it to put headers on a 318?

Headers will improve performance . Back in the 70's headers and an intake on a 318 woke it up nicely , well worth it . Besides HP 340 manifolds will cost more than cheap headers . Some cheap headers are a pain to install and make one plug hard to change , that was years ago though , might be dif now . As to clearance , some claim no problem others pancake the pipes , I has hooker SS headers on my 70 and the pipes were pancaked so I went tight tube hedman . Find out what brand the guys have that don't seem to have ground clearance problems and use them .
Here is small block header comparision on a mild build
http://www.moparmusclemagazine.com/...ers_into_300hp_crate_engine/dyno_results.html
Not a big difference between dif headers and manifolds