Worth it to put headers on a 318?

Too header or not is the question you ask but my question to you in regards to the engine and car set up is what do you want out of it.

What is your 318's compression ratio? Is it enough to support the RPM cam?

Generally speaking, yes it is worth it if max power and a more effceint running engine is what your after. The MM mags link above shows power differences on a larger but much much tamer cammed engine at a level where I myself would not bother with headers since the build is just lame in the power department.

Also, there are much better cams the. The RPM cam that are also designed for use with a exhaust manifolds in use.