TECH: How to make a "Vintage" Tachometer for a '47-53 Chevy Truck

I thought some of you might like this.

After adding a V8 in my ’52 Chevy pickup and converting it to a 12 volt system, I decided I needed some accurate gauges. Since I like to keep things simple, I just added four 2-1/8” gauges (fuel, oil, water and volts) into a panel and mounted it under my dash. Now that I had these new gauges, the truck’s original 4-gauge cluster served no purpose except to fill the large hole in the dash next to the speedometer. But not for long.

One day my buddy Buzz was riding with me and pointed to that “dummy” gauge and said, “You should stick a tach in there.” Which I replied, “That would be cool, especially if I could make it look like a factory tachometer.” After thinking about it the rest of the ride home, I decided I’d do it.
My plan was to take a new Sun Super II tachometer, take the electronics out and put it into the truck’s stock gauge housing. To make this look “period correct”, the new tachometer would need to have the same lettering style, needle, center trim and mounting screws as the speedometer’s. Two speedometers would also be needed to do this. (Luckily I had an extra speedometer that I picked up at a swap meet.) The first one was necessary because I needed the housing, dial and needle to make the new tachometer, the second one would be kept original with the exception of the new dial face decal.

I started by taking one of the speedometers apart and removing the speedo head. This “donor” gauge gave up its metal housing, dial, needle, bezel and glass to make the new tachometer. The Sun tachometer was also taken apart to get the circuit board out. After test-fitting the circuit board, dial and needle into the speedometer housing, I had a plan.

An aluminum adapter was made so I could mount the truck’s original dial onto the tach’s circuit board.


Next, a hole was cut into the metal speedometer housing and four mounting brackets were made to secure the tachometer’s plastic cup. After taking some measurements, the cup was shortened and then installed into the housing along with the circuit board.

The last step was to make the new dial decals. Using Adobe Illustrator software, new speedometer and tachometer dial faces were created, matching the original number style and layout. To make sure the tachometer would read accurately, the numbers were positioned to match those on the Sun tach dial. As a final touch, I added MPH to the speedometer and RPM x 1000 to the tachometer. The electronic file was then sent to a local graphics shop where a set of vinyl decals were made the same size as the dials. The dials were sanded, primed and painted flat black then the new decals were applied.



To keep that “original” look , I also modified the truck’s center dial piece and needle to work with the tachometer. Using a hand held digital tachometer, I verified the engine’s RPM’s so I could reinstall the needle in the right position on the tach. Finally, both gauges were reassembled and installed into the dash.

 

Nice tech article.

 

That's pretty cool!

 

amazing......good job

 

just phenominal!

 

nice job! I love my '53 but hate the dash, I just wish I could come up with a cool replacement.

 

Very clever....good job!

 

Wow! Neat job!

 

Wanna do mine now..? LOL

 

Very nice job..Looks great........

 

Now thats really trick! It was well thought out, took some time, but very doable.
Thanks for the insight and great photos!

 

Great idea, nice execution.

 

Very nice job. I did something similar, but not built into the dash, as yours. I tried to make it look like it could have been a factory accessory.

 

Great job !

 

That is amazing! Thanks for the great tech.

 

Both are great examples of "period" ingenuity.
Cool tech!

 

I like stuff like this, well done!

 

Thats sick! Im gona have to steal your idea on my woman's truck. how well does it light up at night?

 

I'm sending you mine so you can work the same magic. LOL Perfect job, well done!!!

 

Nice job, might have to try something like this in the future. Thanks for sharing it with us.

 

That is great and timely for me. My son and I were talking about getting a tach for his truck and this deffinately is a great option.Thank You.

 

Bitchin'! I really like that! I am working on hiding a high intensity shift light in the stock speedo in my chevy II.

 

Very well done!

 

Good idea, nicely done. Now you've got me thinking.

 

Great work! I'll have to remember this when I finally get working on my '49 Chevy 3600, but I might mod the dash so it's got 3 gauges.

 

Thanks for all the nice comments.

It lights up and matches the speedometer perfectly. Same housing, same dial and same 12 volt bulbs as speedometer uses.

 

Very, very nice application.
Most people that think outside the box, are at least one step ahead of the trends!

 

Both of those are very well thought out and done .

Keep up the good works .

 

Nice job. I will take this into consideration when I look at new gauges for the panel