gripdad

67 Corvette 427/400 stock w/TI transistor ignition was running then died one day. The ignition is not getting a spark except when the key is turned from on to start or start to on and then just one spark usually with a backfire. I replaced the amplifier, TI coil and the magnetic pickup coil. The old pickup coil had bare wires shorting where they exited the distributor and I figured this was the problem. I am getting 12 volts to the amplifier. I get 12 volts to the + coil terminal with the white wire disconnected from the coil and 3.5 volts with the white wire connected to the coil. I only get 7.5V from the pink wire from the starter at the pickup wires with everything hooked up. I removed the distributor and I get @ 1.2V a/c at the trigger wires when I spin the Ti distributor pole piece. I set the distributor pickup gaps as evenly as could. Should I get a trigger every time those 8 points on the reluctor line up? Why isn't this distributor triggering?

larrywalk

You should get a spark whenever the 8 points pass each other (line up). This causes an abrupt change of voltage from the pickup coil which the amplifier uses as a trigger to cut the current in the coil and cause a high voltage spark.