The heat vents in Rob's '70 Bug are further forward than in Dave's '73 SB car -- down near the floor just to the rear of the pedal cluster. In Dave's case it's his left ankle that gets fried; it's Rob's right foot that gets cooked! :-) No complaints! As long as it's warm and clean.
The original vents in Dave's car were equipped with adjustable metal flaps. As with many other things, the flaps were missing, and replacement parts are almost impossible to find (Dave finally obtained used flaps through the VW dealer, of all places!). From about 1972, the heater vent flaps are controlled by a cable (also missing in Dave's car) that runs from the left lever between the seats around just to the rear of the pedal cluster to the vent. Dave replaced the cable with a choke cable (stiff wire inside of a metal coil). It only works so-so, Dave reported; he would prefer the earlier manual flap system like Rob's.
In Rob's car the front heat vent flaps system is manual. The whole fitting is plastic and has two screws through the carpet holding it in the heater channel. In his ‘68 Bug system is even simpler - the vents are cut straight from the heater channel side and bent into the channel, so they angle the air out. The closure flap is just a metal slide over the vents.
In really cold weather Rob can shut everything down except the windscreen and the side foot vent, for best heating where it is needed. In Dave's later system, pushing the lever lever down shuts off all 4 floor vents, so the heat (pulling up the right lever) all goes to the windscreen. The floor vents are all-or-nothing, where the earlier system allows you to select which front and rear floor vents get warm air.
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