Resetting Tach...???

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Jan 10, 2003 | 11:06 PM

DR76

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From: Florida

Resetting Tach...???

Since I've got the '95 LT1 in my '76, I don't know if this is a C3 or C4 question, so I'll post in both places...

My tach is reading about double what the engine is actually spinning...is there a way to reset the tach?

Thanks!

Dr. :banghead:

Jan 10, 2003 | 11:21 PM

Smokehouse69

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From: Semper ubi, sub ubi

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Re: Resetting Tach...??? (DR'76)

Here's a link to a support page on Zip's tech support page, that was originally published in Corvette Fever magazine. On 75 and 76 tachs you must re-zero your tach, the article describes how to do it.
http://www.corvettefaq.com/c3/RebuildSpeedo.htm

Jan 11, 2003 | 11:03 AM

DR76

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Re: Resetting Tach...??? (Smokehouse69)

Thanks...now if I could only go back in time, to '75, and slap some engineers around who designed this, that would make my day :smash:

I appreciate the info...off to the garage I go

Dr.

Jan 11, 2003 | 08:15 PM

DR76

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Re: Resetting Tach...??? (DR'76)

I guess I'm actually OK as far as zeroing my tach...it does jump right to zero when the key is turned on, but does read EXACTLY double of what the engine is actually doing (verified thru DataMaster - a computer reading program LT1's use)

Is there a "filter" or "Multiplier/reducer" these tachs can use?

Thanks! :cheers:

Dr.

May 3, 2020 | 06:46 PM

TO_Vette

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From: Thousand Oaks Calif.

In my 1981, installing my tachometer. I lost my needle so ordered a new one. What I'm noticing is that when I pulled the old one out it took some effort but putting this one in requires nearly no effort. I've pushed in and don't want to push too hard and break it. Should I hear a click or is there someway to make it sung ?

Also, read and seen the Wilcox video on how to zero out the tach. I've turned the ignition on and put the needle on set at zero a dozen times. Each time I start the car and it is nowhere close to zero.

Any suggestions?

May 3, 2020 | 10:06 PM

jackson

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From: Unreconstructed, South Carolina

So ... where does the 95 LTI Tach Out signal emanate from ?
On a 76, signal comes from block mounted distributor's cap (coil).

I'm no optifart guy and not interested in joining ... but me thinks that motor's ECM is a "batch fire" system ... if tach signal comes from a source that fires less than once per cylinder ... then well ...

May 3, 2020 | 10:12 PM

TO_Vette

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From: Thousand Oaks Calif.

The problem isn't the signal, its that the needle isn't sitting snug. Trying to see if this is a bad needle or is there something or someway to make it tigher?

May 3, 2020 | 11:18 PM

jackson

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From: Unreconstructed, South Carolina

Quote:

Originally Posted by jackson

Quote:

Originally Posted by TO_Vette

The problem isn't the signal, its that the needle isn't sitting snug. Trying to see if this is a bad needle or is there something or someway to make it tigher?

My comment was for the OP, not a hijacker