FBO ignition box problem

[carrman]

So I installed a new FBO HRR688 box and pertronix coil in my Newport. Everything works fine except for my auto meter sport comp tach which quit working. Any ideas? It twitches when I start the car but after that it does nothing.

 

[65sporty]

It's on the Neg side of the coil right.

 

[carrman]

It is now. Rich had it wired to a lead off the distributor. Works now, but reads a touch slow.

 

[carrman]

So, I'll bring this thread back from the dead since it's mine...;-) My tach never worked as well as it used to before the FBO box. Well I can across a diode that came with the box, and it's to be installed inline with the wire form the coil to the tach. Installed it today and what a difference it makes. Its back to working normally.

 

[LocuMob]

So, I'll bring this thread back from the dead since it's mine...;-) My tach never worked as well as it used to before the FBO box. Well I can across a diode that came with the box, and it's to be installed inline with the wire form the coil to the tach. Installed it today and what a difference it makes. Its back to working normally.

Instructions.

Glad it's working correctly.