When I bought my '73 Vega last year it had a 3-speed manual transmission in it. I had never seen a 3-speed in a GT, but the seller threw a 4-speed and shifter into the deal and all was good.
Last week I finally got around to pulling the 3-speed and installing the 4-speed. Everything fit just fine, but there is no provision anywhere on the 4-speed case to plug in the Transmission Controlled Spark switch that was on the 3-speed
Do I have a 4-speed from a different year? Will the car run poorly because that switch is not in place? (I haven't run the car down the road because I also took the gas tank out to work on the sending unit) How important is that switch?
As I remember there should be a solenoid that the switch controls to limit vacuum advance to the distributor until it is in high gear. Just bypass the solenoid and right to the vacuum advance with the vacuum hose
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