There are four ways to find a ratio.
1 A dealer can normally tell from the vin number.
2 There are normally tags or labels on the axle that have part number, gear ratio, and fluid requirement
info.
3 You can count how many times you have to turn the driveshaft to get one complete turn of the tires.
4 You can divide the number of teeth on the ring gear and divide by number of teeth on the pinion.
The gear ratio for the 1979 Mustang V8 is 2.47:1
The axle ratio on a 1998 Mustang Cobra is 3.27:1
3:31
The axle ratio on a 2007 Ford Mustang GT is 3.55:1
2.73
it has an 8.8 rear end with a 3.23 ratio.
The gear ratio in the 1979 Ford Mustang turbo four is 3.45:1
3.31
Typically 2.73 but it depends on if the original owner had another gear ratio put in during the manufacturing
The gear ratio for a 1988 Mustang is 3.45:1 on a standard (four) and 3.73:1 optional (four)
Should be 3.27
If you call a GM dealer and give them the VIN# they can tell you what gear ratio you have.