I want more Hp for my 318

I bought a 67 Cuda and love it, except for the lack of power. The car runs great but I think I can take it in my Dodge mini van. It has a beautiful 318 with a Edlebrock Performer manifold, a 670 CFM Holley 4 barrel carb, dual exhaust, 8 3/4 rear end, and a TCI tran. Some day I may drop a new engine in it but for now I would like to install a CAM and/or headers. Does anyone have any thoughts or experience and is this a waste of time and money for a 318? What do you think I will gain, another 75 hp?

I like that 268 comp mentioned below. Your compresion ratio is an unknown and probably low. If the engine is in good shape, I'd mill and pocket port the heads with that cam and install heders with a 2-1/2 pipe. The carb is fine, alot, but fine.

You have a 8-3/4 rear, but you never mentioned the gear ratio or tire size.

Between the cam and preped heads and headers, you'll gain the HP your looking for.