Best way to add factory tach and center gauges?

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Location
Missouri
My Car
1971 Mustang Convertible
1971 Mustang Mach I
1972 Mexican GT-351
1971 Mustang Convertible
1988 Bronco II
1970 Torino 4 door
I have a 71 vert that did not come with a tach nor the center gauges. I have the factory tach cluster (fuel and speedo). I have a couple of factory center gauges. What is the best way to go about adding these? Do a tach conversion? Sounds like Ford had remedial wiring designers put these together but maybe things have changed.

 
There's some bozo on the website that does conversions from standard to tach wiring.  From what he told me, he can't convert the headlight harness, but the only thing that changes are the two ammeter lines; most people convert the ammeter to a voltmeter via RCCI (Rocketman Classic Cougar Innovations).  If you want the proper headlight harness, the only reproduction is for the Mach 1 (tach), but it comes with the sportlamps.

For some reason, I can't remember this bozo's name...Midnight maybe? 

 
There's some bozo on the website that does conversions from standard to tach wiring.  From what he told me, he can't convert the headlight harness, but the only thing that changes are the two ammeter lines; most people convert the ammeter to a voltmeter via RCCI (Rocketman Classic Cougar Innovations).  If you want the proper headlight harness, the only reproduction is for the Mach 1 (tach), but it comes with the sportlamps.

For some reason, I can't remember this bozo's name...Midnight maybe? 
Lol. Just trying to figure out the best way without trying to source the "correct" harness.  My vert has the deluxe grille so I got that in my harness. I am just looking for what makes the most sense without incurring a large financial deficit in the process. 

 
Your cheapest way is to use the Bozo's services, which will run about $325 plus another $50 or so for RCCI's work.  Just the headlight repro runs $400.  You'll also need a new repro alternator harness (~$35). 

 
IMHO, if you want a top-shelf install, talk to @TheRktmn and @midlife first, then figure out the best way to proceed.  In my case, this is what I did before I ever knew about RCCI and Midlife....

My car came with the instrumentation package (center gauges), but only a clock where the tach should be.  We hunted down a tach cluster and stumbled on an extra non-tach connector.  Since nobody sold replacement connectors (at the time), I took the 18-pin non-tach connector, cut out a section in the middle, and JB Welded (I know, don't laugh :classic_blush: ) it back together so it was a functional 12-pin tach connector.  I reverse engineered the pinout differences between the two connectors.  It was relatively simple to pull the pins out of non-tach connector and plug them into my new tach connector.  

I also had to tap into the circuit going from the ignition switch to the coil (right behind the tach) and put a 2-pin connector (you can get this at any auto parts store) in series for the tach signal itself.  

Here were my takeaways:

  • The only negative I found with making my own 12-pin printed circuit connector was, the wiring to the connector on an actual tach wiring harness is a slightly longer than the non-tach.  This makes it a tight squeeze to un/plug the cluster.  Luckily, I don't remove it that much any more and this was a LOT less work than extending the wiring and WAY cheaper than replacing the entire harness.
  • If I had to do it all again today, NPD now sells the 12-pin printed circuit connector (part number 14489-9A).  No need to mess with JB Weld.  Plug and play.
  • Splicing into the tach signal was pretty easy, but don't be tempted to use crimp connectors, solder and heat shrink it!  If you don't have the skills/tools for that, find someone who does (beer can be a great currency).  If anything in this circuit opens, your engine won't RUN (i.e. engine just dies)
  • Make yourself a 2-pin jumper.  Remember where I said "If anything in this circuit opens, your car won't run"?  This also means that, if your tach fails, your car won't run.  If that happens, just reach under the dash, pull the 2-pin, plug in your jumper and drive home.  I found a convenient place under the dash to clip in my jumper (it would just get lost in the console/glove box).

There, that's my story.

Good luck,

Nick

 
I'm just going to through this into the hat so to speak. If you car came with idiot lights. why not forego the factory tach and all the install issues that go with it, and do as I did. Have Bob at Rocketman's Classic Cougar Innovations convert your idiot light segment to his tach conversion with idiot lights. Then for the center gauges, go aftermarket and choose mechanical for oil and temp with a volt meter that is simple to connect to any 12V keyed source. There have been many threads and posts on building and installing center gauges. The choices are many. If you prefer to keep the original electronic gauges, adding the correct senders is quite easy. Below is a couple of pics of mine. ( Ok I know, the cubby box is upside down, been corrected by dumbass)

IMG_0220.1.JPG

IMG_0218.1.JPG

 
Thx for everyone's inputs. I guess I need to save a little money or sell some parts from my parts car!

 
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