Reply to "Weber carbs - owners speak out"

They are more sensative, actually the engine is, because it is an IR and each cylinder has it's own carb. There is no community plenum for them to share and average out the changes.
I always found it interesting that the Holley Carb size chart does not apply to an IR setup. A typical set of 48IDA's is flowing around 2400cfm.
They are also very sensative to reverberation in the manifold. If you are going to seriously try to tune them you should limit the cam overlap to 30 to 35 degrees. In other words a special "weber cam".
Big overlap cams don't work well with them. The overlap on the exhaust actually reverses the flow of the carb and blows it back out of the stack.
Another caution, make sure that you use high pressure fuel inlet valves, low fuel pressure (3psi) and heat isolating gaskets. If you don't when you shut the enging off hot, the fuel will perkulate like in a coffee pot and turn into "old faithful", the geiser.
Want to see your hot engine swimming is gas? It'll take years off of your life.
I'm sure there are a couple of little things I left out but you'll have a wonderful time experiencing the wonderful world of weber on your own. Enjoy!