The Maniflow steel intake manifold has established the standard by which all others measure themselves. This manifold is specially designed to maximize air flow within the space requirements of a Mini. It accepts either twin 1 1/2" or twin 1 3/4" carbs but has a 1.5 bore size. (Twin 1 3/4" carbs should only really be tried on a full race engine!and if you need a 1.75 bore size order C-AEG491).