ok thanks guys, i was thinking of using a single carb for simplicity

The best manifolds are the sidedraught ones.

Generally if each cylinder bore has it's own throttle body you provide the potential to produce more power.

To then utilise that potential you need to work the rest of the motor cam, ignition, head, exhaust etc.

If you throw twin carbs straight on a stocker you will see a significant power improvement although tuning may be tricky. But even then you will not benefit from the full power on offer by the carbs as the engine is not prepped or work to take advantage of them (the carbs).

Twin SU's are fairly cheap compared to twin barrel sidedrafts.

Regarding the A-series manifolds there are different types and I can't remember the details but one particular manifold flows better than the rest, this is the manifold that has a concave bowl in the manifold below the carb platform (I think it's the H95) The G51 is the drop down type that doesn't flow as well as the others.

The flow difference is very minor but there is a difference.

G51 is Vanette, it has a different (slightly) angle for the carburetor. click for more details

The best carburetors for stock-to-midle is Hitachi Twin Carb
The best for stock-to-wild is twin DCOE (weber, dellorto or mikuni/solex)

there is a couple of A series manifolds on gaybay that look vastly different, does anyone know the pros and cons between the G51 intake and the H95 intake?

Also what benifits does twin carbs have over a decent single carby?

More importantly what carby combination would best suit a mild A14?