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Replacement Speedometer / Tach - Please Help!

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Old Dec 1, 2009 | 11:59 PM
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foseguera's Avatar
foseguera
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From: Mountain View CA
Default Replacement Speedometer / Tach - Please Help!

Hi All,

I have a 1975 C3 with a L48 and when I tried to replace the accelerator cable, I wound up breaking the orig speedometer (after removing the dash). I would like to replace the tach and speedometer with aftermarket gauges. I have been finding trouble deciding which brand to go with / what gauges I should choose. How is auto meter? I believe I have a mechanical 5in speedometer and an electric 5in tach. Below is what I am considering purchasing; what are your thoughts?
Also, if I am not using the OEM speedometer or tach, how / where do I install the turn signals, brake lights etc? Any feedback is VERY much appreciated!

Semper Fi

Felix

speedometer $129.99:

Auto Meter #105-5154

Pro-Comp In-Dash Speedometer
5" mechanical
160 mph
Resettable trip odometer

Tachometer $139.99:

Auto Meter 5160 - Auto Meter Pro-Comp Gauges

Pro-Comp In-Dash Tachometer
5" electrical
10,000 RPM

Last edited by foseguera; Dec 2, 2009 at 12:04 AM. Reason: Forgot to add information for request.
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Old Dec 2, 2009 | 12:26 PM
  #2  
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tigers123
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From: belle plaine ks
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Any aftermarket 5 inch speedo will fit. If you are using a cable driven unit you need to go to your parts store and buy a speedometer cable for a 1968 corvette. It will be the right length, but more importantly it will have the screw on end for the speedometer head instead of the push in kind that is on your car. Also you will need to make a shim or I call it an adaptor that will go around your new speedo and adapt it to the mount where your old one goes. There was a guy who had some made up one time for some of us the forum. They were made on a water jet machine and were really nice. There is also a pattern floating around out there with the info on how to make it. Maybe some of the other forum members who have made the swap can help me find that for you.
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Old Dec 2, 2009 | 01:11 PM
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foseguera
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From: Mountain View CA
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Originally Posted by tigers123
Any aftermarket 5 inch speedo will fit. If you are using a cable driven unit you need to go to your parts store and buy a speedometer cable for a 1968 corvette. It will be the right length, but more importantly it will have the screw on end for the speedometer head instead of the push in kind that is on your car. Also you will need to make a shim or I call it an adaptor that will go around your new speedo and adapt it to the mount where your old one goes. There was a guy who had some made up one time for some of us the forum. They were made on a water jet machine and were really nice. There is also a pattern floating around out there with the info on how to make it. Maybe some of the other forum members who have made the swap can help me find that for you.


Thanks so much for your reply!
-- I don't understand why the shim / adapter is necessary?
-- Where does it go?
-- Shouldn't the new gauges fit where the old ones were?
-- Where do the ports / lenses for the turn signals, brakes, etc go? From what I can tell, the old speedometer / tach has them embedded?
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Old Dec 2, 2009 | 01:54 PM
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1Fordman
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From: Marina CA
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Originally Posted by foseguera
Thanks so much for your reply!
-- I don't understand why the shim / adapter is necessary?
-- Where does it go?
-- Shouldn't the new gauges fit where the old ones were?
-- Where do the ports / lenses for the turn signals, brakes, etc go? From what I can tell, the old speedometer / tach has them embedded?
The Autometer gauges are not a direct bolt in. You need the shim/adapter between the existing gauge tunnel and the Autometer gauge for it to be held in place.

There are openings in the original tach/speedo where the bulb sockets fit into for the brake warning, high beam and turn signal indicators. You'll need to design/fabricate a way to have these indicators.

You may consider Dakota Digital gauges if those may be of interest to you.
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Old Dec 2, 2009 | 02:27 PM
  #5  
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tigers123
Burning Brakes
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From: belle plaine ks
Default Adaptor for speedo and tach



This is what it looks like. You have to put the aftermarket speedo inside the hole. The tiny holes on the outside edge bolt you up where the factory tach or speedo mounted. And yes you do have to move your turn signals and high beam indicator. You can drill the web on the adaptor plate and put small led lights in there. They come in colors and are available at autozone etc. It isn't that bad a swap. The hardest part will be taking the dash apart. If you need a tracing of the adaptor plate, pm me with your address. I tried scanning the plate with my flat bed scanner, but when i went to print it out, it came out the wrong size.
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