I have a 904 trans with a 391 rearend, could anyone tell me how many teeth on the speedo gear would be correct one for the application?

 

What size tires ? Probably about 38-39

 

Gents -

Anybody have a chart for gear size relative to rear end ratio and tire size?

Tks

Archer

 

Mopar Speedometer Pinion Numbers
Axle Ratio Overall Tire Diameter

...........24".................... 26"................. 28".................... 30"
2.76 2538930(Yellow) 2538928(White) 2538926(Red) 2538924(White)
2.94 2538932(Black) 2538930(Yellow) 2538928(White) 2538926(Red)
3.21 2538935(Orange) 2538933(Yellow) 2838931(Green) 2838929(Black)
3.55 2538939(Green) 2538936(Red) 2538933(Yellow) 2538931(Green)
3.91 2538943(Blue) 2538940(Orange) 2538937(White) 2538935(Orange)
4.10 2538945(Yellow) 2538942(White) 2538939(Green) 2538936(Red)
4.30 2538944(Black) 2538941(Red) 2538938(Blue)
4.56 2538945(Yellow) 2538943(Blue) 2538940(Orange)

Last 2 digits are tooth count


Tire size calculation:

Tire Size: 245/60/15

245mm/25.4mm = 9.64 Inches Section Width

9.64 in. X 60% = 5.79 in. Side Wall Thickness

5.79 in. X 2 = 11.57 in. Total Side wall height

11.57 in. + 15 in. (Rim Size) = 26.6 in. Diameter

 

340 -

Cool, tks!

Archer

 

I beleive that they are 235/60/14

 

I beleive that the tire size is 235/60/14. the car is at my buddies house so i can not check the size for sure. Thanks for all the replys.