There is no advantage in removing the charcoal cannister fuel vapor recycling system, if you plan to stay with the original engine. It not only allows fumes from the evaporating gasoline to be sent to the manifold to be burned but also relieves pressure in the fuel tank in a controlled fashion. Stick with the original engine and have it rebuilt with an .030 or .040 over bore and a Weber 2 bbl downdraft carb and an early header. "Detox" i.e. remove all other anti-pollution control items, including the cat and you will have plenty of clean, cool power and ecconomy and still have a "real" B. Go to The MG Experience web site for more info & good illustrations.
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