I meant to disconnect the vacuum secondary actuatin link or temporarily block the vacuum port to them. I suggest doing that unless you have a single four barrel top for the tunnel ram. Four primaries at once would be like having a double pumper with four corner idle adjustment but split across the plenum. Fuel distribution would probably get really sloppy feeding from one end or another on the opposite end on a T ram. But I think that much vacuum signal to the carbs and the light springs are causing the bog. The secondaries are opening like a light switch and the vacuum is falling out past the point of pulling fuel until half track when the revs finally come back up.
