solex versus weber carbs, is there a big difference ?? Options

[jimkelly]

is one brand superior to the other ?

Jim

[lapuwali]

Actually, Al, you have that reversed. The early Solexes used a solid shaft, and the only way to correct imbalanced airflow through each throat was to bend the shaft. The later carbs had a split shaft with a screw adjuster, so you can balance them on the car by just twiddling a screwdriver. That said, the adjustment mechanism on the split shaft carbs tended to break after 10-20 years, which was never a problem with the solid shaft models. However, by that time, you usually needed to rebush the throttle shaft holes in the carb bodies, anyway, which means removing the shafts.

The split shaft carbs didn't appear until the 912 was out. 1968, I think.

Oh, and both Solexes and Webers are smaller above the throttle plate, as that's where the venturi is, which is by definition smaller than the throttle. The Webers have easily replacable venturis in many sizes, up to about 36mm for a 40mm IDF. The Solex PII-40s that the 912 used had a 32mm venturi, which was pretty big for a 1600. The Type IV 1.7 usually uses a 28mm venturi, where the 2.0 uses a 32mm venturi.