hey guys im new to the forum .ive also had this problem in two different cars the first was a 1979 malibu and mind you this motor was 1979 454 bone stock with performer intake/holley 750 only and i couldnt keep temps below 200 if the car wasnt moving.so i dont believe its got any thing to do with any mods.the cooling system had a 3 core rad/17 flex/stock WP/160 thermo.TODAY IVE GOT A 454 WITH ABOUT 10:1 /268XE CAM/RPM INTAKE/160 THERMO/17 FLEX/4 CORE RAD/AND ONLY 14 DEG INITIAL ADV AND IM HAVING THE SAME PROBLEM.I THOUGHT IT MIGHT BE AMBIENT TEMPS UNDERHOOD SO I ADDED A COWLHOOD LIKE THE FIRST CAR,BY THE WAY THIS IS A 1986 MONTE.SOMETIME TOMMOROW IM GOING TO GET A HIGHER PRESSURE CAP(22)TO SEE IF I CAN SOLVE THIS PROBLEM.IM ALSO THINKING ABOUT A HP PUMP.BUT THE ALUMINUM RAD IS THE LAST ON MY LIST.ANYMORE IDEAS???THESE CARS ARE TIGHT WITH BBC UNDREHOOD.TODAY IVE TRIED THE BIG ELECTRIC APROACH BUT IT SEEMED THE FLEX WAS PULLING HARDER AT IDLE.IVE ALSO GOT THE BECOOL DUAL 11 INCH SETUP WHICH ILL TRY ALSO.