Need help wiring Autometer Phantom Tach and engine backfiring

[cherbi7]

I have a 1986 Rx-7. I purchased an auto meter tach that was used on an Rx-7 but have no idea which wires go where... I have searched autometers website and cannot find any information on the wiring for this. Can anybody tell me which wire goes where. I have a red, green, black, and white wire.

Also I have switched from s4 to s5 intake,installed kill switch, removed all emissions stuff, added header and true dual exhaust all the way back, and removed cold start stuff from throttle body. The car ran fine until I pulled the gauge cluster and added my own gauges(water temp, oil temp, and pressure. Now the car has a really bad lope to it and just pops and backfires out the exhaust when I press the gas pedal. Seems like primary injectors are not coming on or something. I have had this problem intermitently before I did any work to the motor any suggestions? I have checked the obvious vaccuum leaks, compression, coils shoot spark, and looked around for loose wires.
Thank you

[CRallo]

Its there... I seem to remember the site being very helpful but here ya go from memory:

Red=Power
Black=Grnd
Green=RPM Input
White=Illumination

Can't tell you about using an aftermarket tach on a rotary, but if you have an MSD box just use it's RPM output.

[mbuskuhl]

The yellow/blue wire near the trailing coil is where you'll hook the green wire too. Ground the black wire, skip the white wire, and hook the red wire to 12v.

[cherbi7]

Thanks putting it in tonight and hopefully I can figure out whats wrong with it at the same time...

[cherbi7]

Ok Installed tach and works great and car runs fine now. I have found that the small terminal on my four pole switch from the alternater gets very hot (too hot to touch). The wire does not heat up it is actually the terminal heating up. I was just going to put the alternater wire on the big terminal battery side with the battery and leave that side of the small terminal with out a wire.
Question is why is that lug heating up so hot?
Big lug to battery
Other big lug to starter
Small lug to alternater
Other small lug to fuze box
This is my current wiring configuration.
Any help is appreciated

[zchris]

If the wire is not hot but the connector is there is a bad connection. IE high resistance. Get out your soldering iron and fix it.
Chris

[cherbi7]

It almost feels like there is resistance in the switch because I can feel the stud heat up before the connector heats up...