Triumph Repair: GT6 1972, constant velocity, electronic injection

Question
QUESTION: Hi- I am having I think a problem with my GT6 Carbs 1972 Triumph. Good fuel flow, no exhaust backpressure, good spark and correct ignition. I am now ready to pull Carbs and clean check but was hoping you can offer some advice. Is there any performance mods you know of for these Carbs
to make them better? My car will start and rev and idle but will stumble on take off or under any load. Spark plugs look perfect. Last question Triumph performance book recommends leaving Carbs alone even for a race motor!!
Then why do people convert to webers and even Mikuni's if these Carbs are so good? Thank You you have a great site.

ANSWER: Hi Glenn,
These are constant velocity carbs with metering needles. This is the closest thing to fuel injection you can get in a carburetor. It is an air flow controlled metering system. The speed of the air going across the jet is the same from idle to full throttle. The use of a metering needle from idle to full throttle makes it possible to have the correct mixture at any RPM where a fixed jet carb must transition from one jet to another to go through the RPM range.
There is nothing wrong with Webers, Mikuni or Delorto but for the same size carb I will always take a constant velocity carb over a fixed jet carb. I look at them as Fixed jet as predecessors then constant velocity then mechanical injection then electronic injection as the progress in fuel delivery. That is my opinion and I am allow to have an opinion.
Howard

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QUESTION: Thanks for quick reply! You have answered my question about the Carb but I am not sure if my cars problem is Carb? What do you think? Also since I have the Carbs off are there any upgrades you can recommend? Any thing I can do to make them better? Again thank you- Glenn  P.S. What is the purpose of using vacuum from a outlet on top of radiator instead of intake manifold?

Answer
I don't have any upgrades to the carbs and I can't think of why you would need any other than the normal rebuild kit. There are some upgrades in float needle and seats and I have used both and can't say either is better than the other.

I have no clue what you are referring to by "vacuum from a outlet on top of the radiator" Radiators don't have vacuum.

Howard