Book timing has emissions related considerations. If you don't have to pass emissions, throw the book numbers in the garbage. In a nutshell, they SUCK for a performance set up!

More initial timing is in order. Fix the distributor mechanical advance (tons of how to on the web) and it will run better.

Stock 318's get at least 10* initial if I work on them. 340's with a stock cam run nice with 14-18. Bigger cam, usually more initial timing.