Best manifold for ThermoQuad-equipped 340

Stock is good, you can mill the center divider down and gasket match it. I have done that you probably seen the pics of that intake before. I would also block the heat crossover and use one or two of the 1/4" plastic spacers under the carb. The 850 cfm quad is the one you want if it's going on a hot 340 and you plan on spinning it over 5,500.