sb 327 runs bad

68 camaro 327. trick flow heads. edlebrock performer rpm intake. 600 cfm 4 barrel holley. motor lacks power and engine diesels (keeps running) after turned off. dieseling is the bigest pain. unsure of the cam in her.? I have rebuilt the carb and resealed the engine. running about 14 degrees of timing. how can I get the timing better and stop the dieseling? any suggestions.

my 327 would diesel if i advanced the timing more
than 7 degrees. and it would always diesel if i
used less than 91 octane.