I'm having a little trouble figuring out the correct single exhaust to get for my car.
#1: what is the correct intermediat pipe.The one with or without the resonator?
#2: is there a difference in Y pipes for regular and premium fuel cars?
Since no one has answered your question, I'll take a crack at it. I could be totally wrong, but here goes; All 2 BBL V-8 engines used regular fuel. The 4BBL(4V) engines are all '4V Premium Fuel Engines.' The 289 High Performance engine is assumed to be 'Premium Fuel' as well. The 2 BBL engine came from Ford with a single exhaust system. The 4 BBL engines, whether '4V or 289 HiPo' had the dual exhaust system and had resonators from the factory. Now, if the car had the GT option, (again from Ford) it was the same set-up except that the GT model came with the chrome tips through rear valence panel. Now, as for where the resonators were located, they were located near the exhaust outlets on the section of tailpipe from the muffler on back and not on the intermediate pipes. And yes, the Y-pipes are different on the single and dual exhaust systems.