1967 273 cam suggestions

The OP should run a compression check and get back to us. There are some very small flat tappet Oregon hydraulic grinds that come to mind that could be done from a stock cam core that could possibly make a fairly good low end to mid range improvement in that. The small fast rate cams are good, too, but it’s going to need something in the 100-104 ICL range. When your taking a chance on a cam like this being too large,
Howards Cams 710011-12 Howards Cams Street Force 1 Hydraulic Flat Tappet Camshafts | Summit Racing, you may want to start looking at a small fleebay turbocharger to wake it up.