trying to fix speedometer
06-26-2017, 10:01 AM
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Car: 1986 Pontiac Trans Am
Engine: 5.0
Transmission: 700R4
trying to fix speedometer
im having an issue getting my speedometer to read accurately. i took the speedometer apart couple weeks back to replace the drivegear for my odometer. once i installed the new Shapeways gear i just put everything back together. problem is i did not lock the needle shaft before i pulled the needle off, any suggestions to get me speedometer to read accurate? i was thinking about driving the car without the clear lens, right at the point OD engages pull the needle off and reinstall at 35MPH? any ideas?
dont have access to GPS
dont have access to GPS
06-26-2017, 10:44 AM
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Car: 1 Owner 1986 TA with a WS6 package
Engine: 5.0 EFI
Transmission: THM700R4
Axle/Gears: 277 Posi Speedo
Re: trying to fix speedometer
Not sure, but I would drive the car around for a few minutes,park it, then reinstall the needle,if's all well it should return to zero. Me personally,I wouldn't pull the needle while moving.
06-26-2017, 04:05 PM
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Car: 1986 Pontiac Trans Am
Engine: 5.0
Transmission: 700R4
Re: trying to fix speedometer
How does that make the speedometer accurate? The needle will Just return to the same position it started. I need to find a point where I know how fast the car is going and install the needle in that spot
06-26-2017, 06:57 PM
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Car: 1 Owner 1986 TA with a WS6 package
Engine: 5.0 EFI
Transmission: THM700R4
Axle/Gears: 277 Posi Speedo
Re: trying to fix speedometer
I should have worded that a little better,remove the needle before you take a spin,then reinstall the needle at the stop bar.
06-26-2017, 07:26 PM
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Car: 84 TA orig. 305 LG4 "H" E4ME
Engine: 334 SBC - stroked 305 M4ME Q-Jet
Transmission: upgraded 700R4 3200 stall
Axle/Gears: 10bolt 4.10 Posi w Lakewood TA Bars
Re: trying to fix speedometer
If you hold your speed constant during a measured mile (interstate highway) and it takes 60 seconds to cover that distance, then you are going 60 mph. If it takes more than 60 sec, then you are actually going slower than 60. And obviously less time = >60 mph. From there you should be able to figure out the rest.
06-27-2017, 07:28 AM
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Car: 1986 Pontiac Trans Am
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Transmission: 700R4
06-27-2017, 11:07 AM
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Car: 1986 Pontiac Trans Am
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Re: trying to fix speedometer
update: i think i got it to read accurately. what i did was i found a free app for my Android called GPS navigator. and i removed the needle, drove the car until the phone read 60 MPH and reinstalled the needle to 60. it took a few tries while holding the gas pedal steady since the weight of the needle changes the speed so i had to compensate. but either way after a few drives the speed on the car reads what my phone says. OD is kicking in at 35MPH and if im accelerating quickly its reading at 40-45
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06-28-2017, 02:31 AM
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Car: 84 TA orig. 305 LG4 "H" E4ME
Engine: 334 SBC - stroked 305 M4ME Q-Jet
Transmission: upgraded 700R4 3200 stall
Axle/Gears: 10bolt 4.10 Posi w Lakewood TA Bars
Re: trying to fix speedometer
Yes, that will work also.