The A.V.C. Two-Carburetter Conversion for the VW

Recently we had an opportunity to test a Volkswagen fitted with the A.V.C two-carburetter conversion. This consists, in kit form, of an additional Solex 28 P.C.I. carburetter and air cleaner, necessary jets, two patent induction stubs, a balance pipe the A.V.C. patent semi-rotational throttle linkage, which is properly bushed and balanced, the A.V.C. choke linkage consisting of rod and angled arms in friction-free bearings mounted on the fan housing with the existing VW captive nuts, a fuel-line, two blanking plates and all the required bolts, washers, gaskets etc.

This makes up into a very neat installation, with a rigid throttle linkage which enables the carburetters to be correctly synchronised and allows for individual settings of the accelerator pedal, while control of idling speed from the choke control is retained. The kit can be fitted by the average enthusiast owner, using the normal VW tool kit. It costs £35 15s. 0d. or £38 10s. 0d. for a Karmann-Ghia (packaging and postage 5s. extra) and is obtainable from Adams Conversions, who also list a single carburetter/exhaust conversion for the VW at 65s. which incorporated in a Super Sports Karmann-Ghla tuning kit, costs £41 15s. 0d.

We tested the two-caburetter conversion, with absolutely standard engine and exhaust system, on a 1956 VW, original apart from reduced-camber rear suspension, front anti-roll bar, a Dehne fuel gauge, stop-watch carrier, grab handle. Barnacle ash-tray and Perohaus clock on the facia, an under-facia shelf, twin vizors, Bosch spot-lamp, special mats, an illuminated anti-dazzle interior mirror, Albert o/s wing mirror and B.R.S.C.C. badge and transfer. It was run on Shell good quality petrol and had ordinary Michelin tubeless tyres; it had run some 31,000 miles. The car proved completely reliable over several hundred miles, returned 36 m.p.g. and was perfectly tractable and easy to start, and gave speedometer Maxima of 25, 49 and 64 m.p.h. in the gears, equal to genuine speeds of 24, 45 and 59 m.p.h., respectively. We timed it over the 1/4-mile of road used for timing other VWs, employing the same driver and timekeeper. The speedometer read 62 m.p.h, at the end of the measured stretch and the following times shown in the table were recorded, those for other tuned VWs being given for comparison. Times taken without correcting speedometer error more nearly coincided with the A.V.C. claims – W.B.