I am running a 700r4 tranny in my 85 camino. The issue is my speedometer is reading 10 miles fast. I know I can play with the out gear and fix it, but I am planing on running a bigger tire size other than the stock 14" one. Does anyone know what size I would have to go up to get it close.

Sounds to me like the speedo. Probably the needle got bent from going too fast in reverse. Need to go 10 mph over the speedo upper limit to reset it. Seriously, the problem started when you changed the transmission? It's always 10 mph fast or it reads 50 when you're going 40? I think you'd have to increase the wheel/tire radius too much to make up a 10 mph difference, especially at low speed. Seems like I read somewhere about speedos getting magnetized and reading high. How many miles on it?

Every tooth on the drive gear(one that is smaller) is about 10 MPH there are several web sites to look at to figure out the ones you need /Also i have a few new gears/ the drive gear and the driven gear,i also have an extra housing to hold the Drive gear, also not all gears will not work in the housing,stamped on the side of the Drive gear housing is the Numbers that will work ,maybe Tranny Mike can chime In .

:texas::beer:

This is where I got mine from. I called and the were very helpful. I cost like $20.00
http://www.transmissioncenter.net/speedometer_calibration_______va.htm?gclid=COmWrae lpqsCFWK4tgodrBpB1g

SsUpPoErRt, Thats a great place for this Info !! Good Job ! :You_Rock:

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