Need help with tachometer wire

[Steve Kaiser]

I installed a tachometer today but the green wire is supposed to go to the "tach" terminal on the coil and there's already a wire attached to that terminal.  It seems to go to a pressure switch (?) or what looks like a pressure switch on top of the back of the engine.  81 Chevy 350.  Any ideas what that is?  Should I splice onto that wire with the tachometer?

[Daniel Long]

Short answer is to just splice the wire or just go right into the contact in the HEI coil cap on the left side and install it there. My Chevy P30 RV didn't have a tach either and I just clamped a "male" terminal end on the wire and put it up into the "tach" terminal. Now you could just splice both wires into one male terminal end and do the same. Each gauge or sensor should get the same readings.

[Steve Kaiser]

Thank you- I shall do that.