NosAvrenim
Well-known member
- Joined
- May 10, 2010
- Messages
- 115
After too many weekends of thinking about installing and fretting about how difficult it might be, I finally set aside Sunday afternoon to install the Retrogauge Mini-tach in the dash. Like most things, it wasn’t nearly as difficult as I originally thought it might be – particularly the wiring.
I’ll try to post some pics later in the week (completely forgot to have the camera close by as I was doing the install). That said, the instructions that came with the tach were simple and straight-forward. The most challenging aspect was figuring out how/where to wire in the ground and fused wires. Doing a few searches yielded no real-world instructions for wiring it in, so here is a quick write-up. Hopefully this write-up will help some other folks down the road.
Requirements: 2 ring style connectors, 4 female spade connectors, 18ga wire (ideally three colors, but I used two – all that I had on hand), pliers, Phillips screwdriver, wire cutters, ¼” split loom.
After reconnecting the battery and connecting the dash panel to the under dash wiring harness, I started the gal back up and the tach seemed to be working well (idle was about where it should be). I haven’t compared the tach to a dwell/tach analyzer yet to test for accuracy, but that’ll come as I tune carb in the next couple of weeks.
While I’ve done some electrical trouble-shooting (fuel sender) and swapping of components (ignition/coil), this was my first attempt at wiring in a new component. I’d love any thoughts on what I did and if anything could be a problem down the road.
I’ll try to post some pics later in the week (completely forgot to have the camera close by as I was doing the install). That said, the instructions that came with the tach were simple and straight-forward. The most challenging aspect was figuring out how/where to wire in the ground and fused wires. Doing a few searches yielded no real-world instructions for wiring it in, so here is a quick write-up. Hopefully this write-up will help some other folks down the road.
Requirements: 2 ring style connectors, 4 female spade connectors, 18ga wire (ideally three colors, but I used two – all that I had on hand), pliers, Phillips screwdriver, wire cutters, ¼” split loom.
- After removing the instrument panel from the dash, disconnecting it from the speedometer cable and under dash wiring harness, I set to removing the cross-hair blank from the panel.
- I then installed the new mini-tach. It fit right in and used the original holes and screws to secure it.
- Next, I wired the ground terminal on the tach to the ground post for the dash voltage regulator using a female spade and ring style connector.
- For the fused connection, I ended up using the connection on the wiring harness for the dash clock. Checking the shop and owner’s manuals, this connection has a 7.5A fuse (the tach instructions call for a 3A, so I may need to change this out). While this is a convenient connector, it’s female and requires a stud (no pun intended). Rather than cut the original harness, I crimped a female spade connector so that it tightly fit into the connection and secured both with a bit of electrical tape. Another female spade connected into the mini-tach.
- For the signal wire, I ran a wire through an existing hole in the firewall and connected it to the “-“ terminal on the coil. Since I swapped the stock ignition out for Pertronix, I had some concern about compatibility, but the instructions from Retrogauge said that the tach was compatible with my setup. So with fingers crossed, I hooked it up and covered the wire with a bit of ¼” split loom to make a cleaner look under the hood.
After reconnecting the battery and connecting the dash panel to the under dash wiring harness, I started the gal back up and the tach seemed to be working well (idle was about where it should be). I haven’t compared the tach to a dwell/tach analyzer yet to test for accuracy, but that’ll come as I tune carb in the next couple of weeks.
While I’ve done some electrical trouble-shooting (fuel sender) and swapping of components (ignition/coil), this was my first attempt at wiring in a new component. I’d love any thoughts on what I did and if anything could be a problem down the road.
