I have a 93 FD with PFC and MSD Igntion with a autometer RPM gauge. Currently the gauge has been plugged into the rpm output on the msd box. But it will not give me the correct rpm. So I think, that's fine, I'll just tap into the rpm signal on the pfc, WRONG. The wire is there but nothing is connected to it...

So either:
A) nothing has to be, it's just an output
B) how the heck is my commander giving me the correct rpm?

I searched, but not many guys use aftermarket tacks. I have a custom gauge cluster with all autometer gauges, I'll post picks when she's back together.

Guess my question is, where could I get a good rpm signal from?

-charlie

 

What wire were you trying at the PFC? The RPM/Tach output is wire 2B

 

i'm going to try 2B

 

why was this done in the first place? What advantage is there? And what MSD ignition are you running, you know that you need 3 MSD 6A/6AL boxes?
you could've at least picked reliable aftermarket gauges... I know it sounds like I am trolling or giving you a hard time, but you need to realize that that kind of rewiring of the interior (on anything but true race cars) usually leads to all sorts of electrical issues. the aftermarket components and connections fail in a fraction of time that the stock stuff did fail/would fail

 

I'm pretty new to rotary's so bare with me. The wiring harness was all but destroyed so the whole car was rewired. It was done with the greatest of care and professionalism.

Could you explain why you need 3 boxes? The MSD was installed on the car at the time of purchase.
-after some research I see that you can run just once box on the leading coils and it makes a huge difference, but if a 2nd on the trailing will help the car live longer than I will buy one asap. Car currently has 750 miles since a total rebuild with a half bridgeport.

 

You would need one for each trailing coil, which would mean that you would need a total of three amps. Not a requirement. If you want a single amp for all the coils just install the HKS twin power.