Weber Carb Differences

[Tom Oxner]

Does anyone know the differences between the weber 40 IDTP 3C1 carb and the weber 40 IDA 3C? Are the parts interchangable? Thanks for you help.


Tom

[E Sully]

Weber Carbs Diff Between IDA IDT IDTP

[Steve@Rennsport]

Hi Tom,

The parts are basically interchangable; the differences lie with the size and position of the transition ports in the bore just below the throttle plate.

The IDT carbs were calibrated more for emissions and a have a leaner "tip-in".

One should always use the same series of carburetor on both sides of the engine.

[1QuickS]

Not only are the transition ports different but the air correction bleed jet for the progression circuit is larger (leaner) than the IDA, IDS and IDAP carbs but this can be changed rather easily. Otherwise all the above carbs are basically identical in performance.

Paul Abbott
PerformanceOriented.com