My old 79 454 in a Itasca model P30 called for 7 BTDC. I always set it just before it would cause PING which was about 15 BTDC. Much greater HP that way. replace the 2 Electronic modules in the distributor. Engine heat cause them to 'Start' to fail about every 2 years. U'll know when the RPM's start to become iradic at idle. Install a TACH. Check the exhaust 'Baffle'. Its at the end of the passenger side manifold. Its a vacuum operated door inside the exhaust pipe. They get burned & stick closed. Check for exhaust manifold leaks. 454's are notorious for that. The only fix is to install the best METAL aftermarket exhaust gaskets U can buy. Many 454's came from the factory with NO gaskets. If U'r 454 is equiped with an exhaust gas Air pump system, Remove the pump, install shorter fan belt, plug or pinch off all 8 air tubes to each cyclinder. That air being pumped into exhaust head makes em run RED HOT. ie; cracked manifolds & exhaust leaks.
