Description 356/912 2 X weber 40IDF replaces Zenith   Performance kit for the Porsche 356 and 912   Webcon performance kit contains   2 x Authentic Weber 40IDF carburettors   2 x manifolds and fittings   2 x air filters   Carburettors are supplied calibrated as follows: venturis     32mm Main jets    125 Air Corr      180 Idle jets     55 E/Tubes     F11   This will work really well on a stock engine, but we always recommend that, to achieve maximum power, driveability and efficiency, you have the carburettors professionally set up on a rolling road. PPO202