GMSports tach/fuel combo alternatives?

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AstroFirebird

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It doesn't seem that GMSports has the combo tach/fuel gauge anymore for our trucks. So instead of paying stupid money for a cluster out of one of the medium duty trucks, has anyone found a place that still sells/makes them?
 
75gmck25

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LMC has a conversion kit for the ‘78 and up trucks. Not sure why it wouldn’t work in an older truck.

I have a tach cluster in my ‘75, and if you bought a new tach and harness from LMC I don’t see why it would be hard to modify an older cluster to add one. The tach wiring is a completely separate pigtail, so very easy once you mount it. Then all you have to do is reroute the gas gauge wiring so you can use a small gas gauge in the lower left pod. I already converted my ‘75 cluster to use a voltmeter instead of an ammeter, and the wiring change was very simple.

To be conservative I might buy an extra used cluster to experiment with if I thought I needed to start cutting things to make it fit.
 
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ali_c20 said:
Try tachman.

http://www.tachman.com/oldsun.htm

There are also replacement circuit boards for the chevy tachs available on e-bay.
Click to expand...

Thanks. Bookmarked this site.

75gmck25 said:
LMC has a conversion kit for the ‘78 and up trucks. Not sure why it wouldn’t work in an older truck.

I have a tach cluster in my ‘75, and if you bought a new tach and harness from LMC I don’t see why it would be hard to modify an older cluster to add one. The tach wiring is a completely separate pigtail, so very easy once you mount it. Then all you have to do is reroute the gas gauge wiring so you can use a small gas gauge in the lower left pod. I already converted my ‘75 cluster to use a voltmeter instead of an ammeter, and the wiring change was very simple.

To be conservative I might buy an extra used cluster to experiment with if I thought I needed to start cutting things to make it fit.
Click to expand...

Yes, you must cut some plastic from the back of the cluster for the tach and fuel gauge to fit. Easy to do, just tape up one end of a bare hacksaw blade, cut it by hand. The plastic cuts easy.

The embossments for the tach rear mounting screws were already moulded into the cluster plastic. (my 1982)
 
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I think some of you guys may be misunderstanding. I’m looking for one of these tachs. Only found on the medium duty trucks, but there were places like GMSports that made them to drop into our light duty trucks. As far as I see, LMC doesn’t sell these.
 

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75gmck25

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LMC sells only the factory style tachs, which do not have the embedded fuel gauge.

However, due to the design of the cluster, we are saying that it’s not that hard to make some minor wiring changes and add a small fuel gauge in the lower left cutout. Most of the time that cutout is blank, or has a clock that hasn’t worked in many years.
 
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AstroFirebird said:
I think some of you guys may be misunderstanding. I’m looking for one of these tachs. Only found on the medium duty trucks, but there were places like GMSports that made them to drop into our light duty trucks. As far as I see, LMC doesn’t sell these.
Click to expand...
Yep, to explain to those who never drove a medium duty, the (normally blank) lower left side gauge is air pressure. So gas gauge had to be added somewhere, easiest solution was to double it up with the tach.
 
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AstroFirebird

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Yup. Instead of the air gauge, I want to have a clock. I also want the tach. The only factory looking option is to use the medium duty tach/fuel level combo. I’m hoping someone still makes one that bolts into our light duty cluster housing. I’m really not too keen on spending $500 on a medium duty cluster that may or may not work.
 
TPISly-C10

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paid mine $100 from a C50 and worth any $$ of it! ;)
 

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I bought a tach/fuel gauge from GM Sports 5-6 years ago. It was a total POS built by a guy somewhere in the Northwest. The plastic housing was poorly done (check out the hole at 7 o'clock), it had a tach needle that wouldn't stay on, and also very poor soldering. A bigger kludge I had never seen!

GM Sports told me to work with their supplier, who promptly sent me another one. Between the two, I got one working but sometimes the tach needle wouldn't fall below 1000 RPM. And I doubted its calibration in the 1500-3500 RPM range where the engine spent 98% of its time. Also, the best I could get the fuel gauge to do (by playing with resistors) was "just above the empty mark" to "just below the full mark". In other words, the needle wouldn't go full sweep. But it did look nice!

The Tachman.com stuff seems to be light years better.
 

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1978-87 Tachometer Conversion Kits

Shop from thousands of parts and accessories to help you restore, maintain, and customize your Chevrolet, GMC, Dodge or Ford truck or SUV. Keep 'em on the road with the right part, right price, right now.
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