The 390 2v had a carb spacer with coolant running into it to help vaporize the fuel. Does the 390 4v have the same spacer? This car has a new Performer manifold and I am about to install the new Holley and need to know.
You're on it Puttsterman. The spacer was for carb ice after warm-up (the choke didn't care as it would just push further open, but the butterflies can't), and the exhaust crossover was for fuel vaporization. While the crossover killed outright power potential, it improved efficiency, emissions and a bit of mileage. I don't use the crossover (nor coolant spacers) with aluminum manifolds, as they get plenty hot without it. Perhaps someone in very cold (crossover) or foggy (spacer for carb ice) areas might like them though.... As I understand it the water was to keep the carburetor from icing up in Winter, though it might have been used to keep the spring in the choke housing warm.