Looking to add a Tachometer
 

So I recently bought an '86 C10 that has had it's factory V6 replaced with a 350 from an early 80's Z28. It has the Saginaw 3 speed with the shifter moved to the floor and I would like to add a tachometer to the gauges.

I am thinking my best option would be to replace the current large gas gauge that is next to the speedo with the new tach and move a new gas gauge over where the blank spot is on the left side. Has anyone done this and can they recommend any specific gauges?

I have seen a bunch where folks have done the entire cluster but that's just not in the budget so I want to find something that looks somewhat factory if possible.

Re: Looking to add a Tachometer
 

Hi There,

I believe you will run into trouble attempting that. Your truck has wiring/printed circuits to match your existing gauge configuration. Some of the earlier trucks came factory with a tach in this location, however you require the wiring harnesses / printed circuits etc. Just my opinion, but you would better off installing a tach in another location.

Re: Looking to add a Tachometer
 

yes your truck has the printed circuit that does not have the tach in it.

realistically you have 3 options:
1- mount an aftermarket tach in another location
2- buy a replacement cluster with correct tach and gas gauge
3- buy the aftermarket tach/gas gauge in one that fits in the stock cluster (http://gmsports.com/trucks)


I actually have one of each in different trucks and I can tell you IMO the original factory setup(#2) looks the best. that said, i don't know if you could get a factory tach in 86 still? so you might have to go with option 3 if you want it in the cluster. I have the combo tach/gas gauge in my 87 tbi truck and it works flawlessly.

Re: Looking to add a Tachometer
 

Thanks for the replies, I will see what the budget will allow and go from there.

Re: Looking to add a Tachometer
 

If you have a local pull a part type place, obtain a 2nd cluster housing with circuit board and the cluster plug. Depending on the place, you can save money by leaving behind un-needed guages. Now you can modify the 2nd cluster with the layout you want. Some Dremel work may be required. Note the year the 2nd cluster is from, and obtain the matching cluster plug pinout. While the plugs are the same for the years of the squares, the pin layout changes. When you are ready for the swap, you can repin your existing truck's plug. You can use pins from the 2nd plug to fill in blanks if needed or to replace pins damaged during the move.

Before the installation, use the 2nd plug to test your connections.

In process of doing this for my 75 using a cluster from an 87 Suburban. Went with the LMC tach in place of the existing gas guage and separate small gas gauge. Adding LED back lights in the process. And a factory voltmeter instead of the dead Amp gauge. At my pull-a-part, gauges are $5 each for the little ones.

Re: Looking to add a Tachometer
 

I have a big truck type tach, and the printed circuit was junk so I used the circuit from my stock gauges setup. All lined up but I just had to solder three wires to the printed circuit and run them to the fuel gauge pins. Worked out fine.

Re: Looking to add a Tachometer
 

anyone know of a tach that fits in the small open spot on the left side of the cluster? i like the big fuel gauge, but wanting to put a small tach in the open location

Re: Looking to add a Tachometer
 

I am looking to put this one in where the clock would go and putting a large 5" tach in place of the large fuel gauge. I am wondering if I can just run the necessary wires to both gauges without using the printed circuits just for those two.

Gas gauge:
https://m.summitracing.com/parts/atm-3314

Tach:
https://m.summitracing.com/parts/atm-3990

Re: Looking to add a Tachometer
 

I just finished this exact setup in my 1987 Silverado V10. Pretty easy to accomplish. I had the large fuel gauge and the clock on the lower left corner. I had bought another gauge cluster from an early 80's with a tach setup with intentions on using the tach and fuel gauge from that setup. I used the fuel gauge but the tach looks too different from my gauges so I ended up with a tach from classic parts. I had to open up a small opening behind where the fuel gauge went to accommodate the tach plug (the printed circuit has a small opening in the proper location so I did not have to cut the printed circuit at all for either the tach or fuel gauge) and i used the original fuel gauge connections to wire back to the new fuel gauge as you can see in the pics (you'll have to cut the original tabs for the fuel gauge on the inside so they don't protrude in too far and are no longer used except to solder the wires to so you can wire back to your fuel gauge). I used the factory tach wire harness that came with the early 80's cluster and it plugged directly into the fuse panel for 12v, used a ground lug that was mounted behind my dash and ran the tach lead to my distributor which already had the connection off the coil unused. Looks great and works very well. Still need to touch up the needles to match the new very orange needle on the tach but overall a very easy project if you take your time.

Re: Looking to add a Tachometer
 

Re: Looking to add a Tachometer
 

Re: Looking to add a Tachometer
 

Or. Just put a small Auto meter tack in the small blank to the left. That is what I did.
I don't need to be looking at the large tach and it makes a simple solution.

Re: Looking to add a Tachometer
 

I was thinking about that as well, was it difficult to install or pretty straight forward? Do you have any pics of your setup?

Re: Looking to add a Tachometer
 

^^This is what I did but purchased the correct font small fuel gauge as part of the swap. IMO, it get the tach in place & looks factory since all the gauges match.

Re: Looking to add a Tachometer
 

Has anyone used the Tach from LMC? It seems like it might be the most economical option.

Re: Looking to add a Tachometer
 

Very nice description and detailed photos mxr515!

Re: Looking to add a Tachometer
 

I have done this. You will need a 5" tach. I used an autometer 5" tach, which fits in there perfectly. I used an autometer fuel gauge as well, and got rid of that little clock that didn't work anyway. For the tach, I just pulled the housing off of one, that was supposed to be a dash mount. Don't be discouraged, its all fairly simple. You just need to wire the fuel gauge over to the correct spots for the new location. As for the tach, all you do is run the wire to the distributor. Honestly none of it is very difficult.

There is only one thing I would advise you to do: Make sure you get a backlit tach. As in, make sure the light shines through the numbers/letters. Not around them. Otherwise, you will have an odd light that can be seen from the passenger side. Which you can't get rid of, because then the gauge face would have no light. I will eventually have to replace my tach with a different one because of this. So you want your tach to be sort of like a modern tach in a new car, for that reason. The numbers/letters/needle are all going to need to be translucent, so that they light up when you turn the headlights on. Basically, the gauge face can't be solid metal. You need to be able to hold a flashlight behind it, and the numbers and lines would light up.

That is the easiest way. Unless you go with a factory tach, but those aren't so great imo. They have a 0 after every number, which just throws the whole thing off.