Speedo gear

[joshka555]

I own an 87 camero. 305 V8 and TPI. My transmission is a 700 R4 from an old minivan, however the person that swapped the transmission also changed the speedometer gear. The gear burned out on me and so I replaced it with tha same size gear not realizing the the drive gear's teeth are larger then the speedometer gear I put in. The gear that I had bought is a 38 tooth and blue color. Does anyone know how I can identify how many teeth should be on the Speedomoeter gear?

[Morley]

Go to a transmission shop and tell them what transmission you have and what your rear gear ratio is and they should be able to hook you up with the proper gear.

[joshka555]

thanks. One more question. Is the ratio engraved somewhere on my axle or anything. I dont know what my ratio is.

[ct91rs]

Originally Posted by joshka555

thanks. One more question. Is the ratio engraved somewhere on my axle or anything. I dont know what my ratio is.

If your car came with a 305TPI and a 700R4, and the rear is stock, I believe it should have 3.23's, but morley would know for sure.

[Morley]

Check inside your glove box. There is a sticker in there with all of your RPO codes on it. Post them here.
Or, jack the rear wheels off the ground, mark the drive shaft with some chalk and one of the tires. Rotate the tire 10 revolutions while counting the drive shaft revolutions. Now divide the driveshaft rotations by ten, this will give you the approximate gear ratio.