How do you figure out what your gear ratio is? i have a 92 Z28 with a 350 TPI, the guy i bought it from said theres a different gear ratio then other 92 Z28's, i was wondering if theres a way to figure it out?

 

One easy way to figure out is to jack the car up underneath the rear housing to where the wheels are just off the ground. Rotate one wheel and count how many times the driveshaft turns to one rotation of the wheel. That will give a ballpark figure.

The other way is not so easy. Count the number of teeth on the ring gear, count the number of teeth on the pinion gear, then divide the number of teeth on the pinion gear by the number of teeth on the ring gear.

Or if your lucky you can get the numbers on the Axel housing and go to www.motortec.com and maybe they have it. Or here tey might have it. Dunno.

 

If he means that the gears have been changed, like that running the RPO codes wont tell you, then there is a way to check it. Jack up the back of the car, put it in neutral, and crawl underneath. Make a mark on the driveshaft, with chalk, or something you can see easily. Have a buddy watch the wheel while you turn the driveshaft. Count the number of times the driveshaft goes around for the wheel to make exactly one revolution. I've done this a couple of times, and if you are precise, it will tell you what gear you have. At least so you can tell a 3.23 from a 3.42 or 3.73.

 

best way is to pull the cover and read the ratio stamped on the gear set, plus it gives you a chance to look at the gears and change the oil.

 

Ede, is this the stamp you are talking about?

Just wondering, because I know that this a 3.73 set, but it dosent say that anywhere. Mabey you have to decifer the serial code or something.

Sorry so blurry, but its the stamp on the side of the ring gear.

 

Or you can do 70mph in D and say your tach reads 3730 rpms=3:73s and so on. Maybe a little off if the stock tire height has changed, but will be close.

 

Stangkiller,

The 11:41 on the end means 3.73s 41/11=3.73 or 11 into 41 = 3.73

 

Man I'm so stupid.