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Electronic tachometers have two things going as far as connectors. First, there must be power to the tachometer, and a ground for that power. Second, there must be a connection to the coil, so the tachometer can count the ignition pulses, which are translated to an RPM reading. The majority of tachometers seen on Type 3 VWs are made by VDO. Almost all of them have connectors marked +12v, +6v, 1, -. Either +12v or +6v are input power for the meter. If both are present (sometimes the case) simply use the correct one for your car. More often only one of these will be present. - is chassis ground. 1 is the connection to the coil. Since no Type 3 harnesses are factory rigged for a tachometer, a single wire must be run from the negative terminal of the coil (the points side) to terminal 1 on the tachometer. Another style tachometer uses a loop rather than a direct connection to the coil. Many Smiths tachometers use this method. For these tachometers, there is still a power input connection, and a chassis ground. In addition there is the loop. Some times this loop is on the rear of the tachometer, but on later models the loop in inside the tachometer case. The connection for the coil is the same for either of these. To connect the loop type tachometer, two wires must be strung from the engine compartment to the dashboard. The negative side of the coil (the points side) is disconnected. The wire from the points is connected to one of the wires heading to the dash. On the dashboard end of the wires, connections are made on both wires to form the loop. The remaining wire end in the engine compartment is connected to the coil. The tachometer senses the pulses through the looped wire, converting them to RPM. The Smith tachometers use blade connectors for power, and bullet connectors for the coil connection loop. Some really early Smith tachometers have studs and nuts for connectors. The latest Smiths tachometers use a single coil wire, in the same way as the VDO tachoÉ}Tagain with a blade connector for power, and a single bullet connector for the coil lead. Smiths tachometers were also made as a combination 6v or 12v, or 12v only. I have seen at lease one Gisson tachometer mounted in a Type 3, and I am sure that other brands could be made to work. It is likely that any tachometer will use one or the other of the connections methods described above. Tim Dapper ------------------------------------------------------------------- Search old messages on the Web! Visit http://www.vwtype3.org/list/