TKO 600 Second Gen Speedometer Calibrate

[73ta]

Running the .64 TKO 600 5 speed with a 3.42 rear gear 25.7" tire. All of the online calculators for speedo gears say to use a 19 tooth driven gear. This makes my speedo read approx 87 mph at 2000 rpm, supposed to be reading 71mph. Tried a 21 tooth. Read 80 mph at 2000 rpm. Still off. I see they make a 23 tooth but say it is limited use. What are you running to get yours right? Could it be my tacometer is off also?

[Craig@Bowler]

Running the .64 TKO 600 5 speed with a 3.42 rear gear 25.7" tire. All of the online calculators for speedo gears say to use a 19 tooth driven gear. This makes my speedo read approx 87 mph at 2000 rpm, supposed to be reading 71mph. Tried a 21 tooth. Read 80 mph at 2000 rpm. Still off. I see they make a 23 tooth but say it is limited use. What are you running to get yours right? Could it be my tacometer is off also?

Have you tried driving with a GPS along to see how that compares. That would be one way to verify what's really wrong. I've seen some strange situations like this before.

[TheJDMan]

If you are running an electronic speedo, you can drive it with a GPS sender. That way no matter what gears or tire size you may switch to it has no effect on the speedo.

https://www.autometer.com/universal-...ce-module.html

[Sbeck09]

If you are running an electronic speedo, you can drive it with a GPS sender. That way no matter what gears or tire size you may switch to it has no effect on the speedo.

https://www.autometer.com/universal-...ce-module.html

How well do those work? My Garmin GPS has a notable delay in showing my current speed when accel/decal. I'm about to come into this issue myself. I don't want to have to wait to see if I'm getting a ticket or not. ;)