Heres the dilema. To get more out of my igntion system I decided to wire in a relay so that when you hit the ignition it activates the relay giving the balast resistor the full voltage. Checked it on a voltmeter and it gains a full volt straight away from about 12.5 -13.5 and on the other side of the resistor from 9.2 to 9.9 (note: measured at idle). So it works. Runs fine and dont know whether or not its in my head or not felt like it started even quicker and felt like abit more mid range response. Now the problem, NO TACHO which is obvious because it gets its signal from the same igniton wire that goes to the resistor.

How can i get the standard tacho to work with the relay directly connecting the battery to the coil?

I have tried a couple of things but ill see what people say first before i comment more.

Thanks