[Rick Parker]

The 48IDA 2 BBl (unlike the 3BBL Porsche variant) does not have provision for balancing the flow between the bores on a single carb. However using small ("ignition wrenches") on the flats of the throttle shaft they can be twisted very very gently in opposite directions to achieve very minor flow differences. This adjustment assumes the throttle plates were properly seated in the bores when being assembled. Keeping the leather bearing seals moist or better yet, using sealed bearings will assist in achieving equal flow.