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Old 06-04-2018, 06:44 AM   #1
Gino
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Default Speedometer calibration

Hi, I had Pasternick rebuild my speedometer. I believe he did a fine job, however there is something wrong. It is about 7 or 8 miles per hour off. Say when I'm going 40 it will read 32 mph. Could the answer be in the transition? I remember something about the gear or wheals we installed. Please advise, thanks Gino
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Old 06-04-2018, 07:39 AM   #2
papanick
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Default Re: Speedometer calibration

EMAIL ME AT [email protected] and I will help you out. papanick
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Old 06-04-2018, 07:49 AM   #3
mfarley
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Default Re: Speedometer calibration

Same with mine until I changed the Speedometer gear. Now it's dead on.
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Old 06-04-2018, 08:54 AM   #4
Synchro909
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Default Re: Speedometer calibration

Before you go replacing the speedo drive gear, you should first see whether the odometer is accurate. If it gives a good figure for a trip over a known distance, then your problem is not the gear. If the figure is not accurate, then change gears. Once the odo is right, the speedo is adjusted internally for accuracy.
I know that because the instrument in one of my cars is good for distance but way off on the speedo and there is no adjustment left. That said, if I travel at the same speed for a while, like on a tour, the speedo eventually gets it right.
Could that be simply a sign that it needs lubrication?
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Old 06-04-2018, 09:50 AM   #5
burner31
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Default Re: Speedometer calibration

Same here, mine reads slower
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Old 06-04-2018, 10:01 AM   #6
duke36
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Default Re: Speedometer calibration

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Some questions: Was it accurate prior to rebuild, rear end ratio (if known), 9-34 or other gears at driveshaft end, overdrive? Did you check it against GPS reading?
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