Tachometer rpm vs speedometer
09-01-2014, 02:11 PM
#1
Burning Brakes
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Tachometer rpm vs speedometer
I have a 64, 327/365 (as many of you know now) and I think my speedometer is off. I am in a 50mph zone and keeping up with traffic(and I know they are going 50) and I am revving 2300rpm on the tach but my speedo says 44-45mph. And when I hit 60mph, I am always looking for another gear. I have a muncie 4 speed but I don't know what gears are in the differential. Does the tach reading match the speedo reading correctly?
09-01-2014, 02:23 PM
#2
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I have a 64, 327/365 (as many of you know now) and I think my speedometer is off. I am in a 50mph zone and keeping up with traffic(and I know they are going 50) and I am revving 2300rpm on the tach but my speedo says 44-45mph. And when I hit 60mph, I am always looking for another gear. I have a muncie 4 speed but I don't know what gears are in the differential. Does the tach reading match the speedo reading correctly?
09-01-2014, 02:51 PM
#3
Team Owner
Take a Garmin or other GPS with you and verify the speed.
09-01-2014, 03:18 PM
#4
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09-01-2014, 04:05 PM
#5
Racer
GPS is most accurate, especially on highway where you can maintain speed for a period of time and vary it as it will take everything else out of equation like tire size, gear ratios etc. You can then get a good idea of % errorRoger
- But the 4:11 is soooooooooooooooo much fun!, especially on a big block!
09-01-2014, 10:05 PM
#7
Racer
If you have an iphone, there is a speedometer app to upload based on the GPS in the phone. I have used that with success to verify my cars speed. Very easy to use.