My brother has a 78 turbo sport coupe regal it runs great ...until it warms up.Then after it warms up upon accleration it spits and sputters then takes off.He replaced cap rotor,plugs ,wires,fuel filter,rebuilt the carb,gutted the cat and put a split 3 inch exhaust on the car.I checked everything i could think of and i am lost as to why once it warms up it runs goofy.If you ease into it it is okay but as soon as the boost gauge shows boost spits and sputters...anybody got an idea?