Speedo pinion to adjust speedometer

[Tori]

Can anyone make a recommendation on a starting point for which pinion gear to swap in to get my speedo more accurate.

Currently at 60mph GPS, car is indicating about 90mph

4.10 gears with 26.8" diameter tire. 904 trans.

I do not at this point know which speedo pinion gear i currently have. If i need to identify this before we can make a calculated guess i will.

Car originally a 318 2bbl with 904

 

[440+6]

http://www.mymopar.com/speedometer.htm

 

[Tori]

Thank you sir ! You rock. Merry Christmas !!

 

[Tori]

Dan @ Brewsters helped me out. Got one on the way. http://www.brewersperformance.com/products.php?cat=277&pg=2

 

[mopar 3 B]

Did you end up with a 43 gear?

 

[Tori]

Dan recommended a 42, but only had a used 41. I went with that because i'm cheap and impatient.

 

[Mjcre]

Is your speedometer needle also bouncing a lot? Mine was off about 15-30 depending on how fast I was going. My speedo needle also bounced a lot. I changed both the speedo pinion gear and speedo cable about a month ago. It fixed both the accuracy and bouncing needle.

 

[hunt2elk]

I have found that a 1 tooth change is about 2 mph on your speedo.

 

[Tori]

Is your speedometer needle also bouncing a lot? Mine was off about 15-30 depending on how fast I was going. My speedo needle also bounced a lot. I changed both the speedo pinion gear and speedo cable about a month ago. It fixed both the accuracy and bouncing needle.

No, luckily needle is steady.

 

[toolmanmike]

https://www.google.com/search?q=mop...d=chrome-mobile&ie=UTF-8#imgrc=PqzCaJdM-8ORSM:

For the next guy.