Need Speedo Calibration Help
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Joined: Jul 2003
Posts: 57
Likes: 0
From: Aberdeen NC
Need Speedo Calibration Help
Here Are The Speedo Readings. How Can This Be Fixed?
And Thanks For All The Help.
Actual Speed / Speedo Reading
10 / 10.82
20 / 20.10
30 / 32.90
40 / 43.90
50 / 56.60
55 / 60.72
60 / 65.90
70 / 78.06
And Thanks For All The Help.
Actual Speed / Speedo Reading
10 / 10.82
20 / 20.10
30 / 32.90
40 / 43.90
50 / 56.60
55 / 60.72
60 / 65.90
70 / 78.06
Melting Slicks
Joined: Aug 2000
Posts: 2,310
Likes: 1
Re: Need Speedo Calibration Help ('75sting)
Looks like you're reading about 10% over actual.
I don't know if playing the ratio would work, but I'd try a speedo gear with 10% more teeth (e.g., if you have a 22 tooth gear now, try a 24 tooth gear).
Just an idea :skep:
I don't know if playing the ratio would work, but I'd try a speedo gear with 10% more teeth (e.g., if you have a 22 tooth gear now, try a 24 tooth gear).
Just an idea :skep:
Drifting
Joined: May 2003
Posts: 1,634
Likes: 2
From: Melbourne, Victoria, Australia, the World
Re: Need Speedo Calibration Help ('75sting)
Here Are The Speedo Readings. How Can This Be Fixed?
And Thanks For All The Help.
Actual Speed / Speedo Reading
10 / 10.82
20 / 20.10
30 / 32.90
40 / 43.90
50 / 56.60
55 / 60.72
60 / 65.90
70 / 78.06
And Thanks For All The Help.
Actual Speed / Speedo Reading
10 / 10.82
20 / 20.10
30 / 32.90
40 / 43.90
50 / 56.60
55 / 60.72
60 / 65.90
70 / 78.06
Where do the "Actual" readings come from?
How can you get 78.06 from an analog gauge?
Do you know your diff ratio?
Wheel size?
In the parts manual(another must have book) it will tell you what speedo drive gear matches what diff ratio with what stock tyre size.
If you dont have access to a parts manual, get the vette in the air and remove the speedo drive gear. Count the number of teeth the gear has.
Go to your Chevy dealer and buy a drive gear with one more tooth and another with 2 more teeth.
Trial and error from there.
If the "actual" reading is accurate you need to slow down the speedo cable revolutions and by adding 1 or 2 more teeth you will bring it into the ballpark (within 1 or 2 MPH)
:cheers:
