speedo gear
Thread Starter
Racer
Joined: Jan 2008
Posts: 291
Likes: 17
From: Woodinville Wa
speedo gear
I have a 63 with a 327 it has a 370 rear end the speedo saids I am going 40mph a speed signal said I am going 30 I am guessing it the speedo gear in the transmission I know they come in different colors how hard is to change one thanks vince
Burning Brakes
Joined: Aug 2013
Posts: 1,071
Likes: 322
From: palm springs ca
Vince,
It's real easy. Remove the speedo cable from the trans and take a 7/16 wrench with you and remove the bolt. Then pull the gear housing out carefully so you don't drop the gear in the trans, and replace the gear.
Dom
It's real easy. Remove the speedo cable from the trans and take a 7/16 wrench with you and remove the bolt. Then pull the gear housing out carefully so you don't drop the gear in the trans, and replace the gear.
Dom
Thread Starter
Racer
Joined: Jan 2008
Posts: 291
Likes: 17
From: Woodinville Wa
This looks like a easy fix you have to find out what color you have now some sites say and a tooth for every 5 mile over you are some say 1.5 for tooth. this is for the drive gear the is also a driven gear on the tram shaft that may need replacement It also depends on the rear end and tire size. I don't think it as simple a color but it could be anymore advise helpful thanks vince
Race Director
Joined: May 2000
Posts: 12,712
Likes: 2,271
You need to provide more data. First how do you know it's a 3.70 axle. Have you counted driveshaft revolutions for one wheel revolution?
There are two types of speedometer error - gain and offset. Gain error is when the percent error is about the same at every speed, so you need readings at 20 to say, 80 in ten MPH increments.
Offset error is when the actual speed error is constant at all speeds.
Sometimes error is a combination of the two.
Also, you need to state the tire size and revs/mile if you know them.
Without the information I'm requesting all anyone can do is guess.
Duke
There are two types of speedometer error - gain and offset. Gain error is when the percent error is about the same at every speed, so you need readings at 20 to say, 80 in ten MPH increments.
Offset error is when the actual speed error is constant at all speeds.
Sometimes error is a combination of the two.
Also, you need to state the tire size and revs/mile if you know them.
Without the information I'm requesting all anyone can do is guess.
Duke
Last edited by SWCDuke; Aug 25, 2019 at 10:51 AM.
Pro
Joined: Jun 2011
Posts: 588
Likes: 41
From: Ohio
The very first thing to know is this an early or late 63. Early 63 had Borg Warner trans and late 63 had Muncie's. Early Borg trans gears are completely different gear sets than the Muncie.....ask me how I know
Safety Car
Joined: Feb 2006
Posts: 4,142
Likes: 704
https://www.cartechbooks.com/techtip...e-speedometer/
http://www.stl-vettes.com/65vette/gearcalc.htm
http://www.stl-vettes.com/65vette/gearcalc.htm
Last edited by buns; Aug 25, 2019 at 03:15 PM.
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