[ted]

When installing vacuum secondary carbs that were not originally designed to be used in pairs, it's important to change out the secondary diaphram springs to lighter units as the air flow through the carbs cuts in half when using two carbs instead of one. Ford used the long yellow springs as the starting point in their two four carb setups. An extra touch is to install vacuum secondary covers that allow both carb secondary diaphrams to be connected by a common vacuum hose so that the secondary opening is synchronized.