I intend this page to be used to be a quick reference to Formula owners, or People who are just interested in the 3rd Generation Formulas. The following is a way to tell what year a Formula is just by walking up to it and waking around it once, without looking at the VIN.
Here is what to look for:
1987
The 87 Formula is the only year to have a non serpentine belt engine, and is also the only year to have the 3 spoke steering wheel. It would also be the only year to have an 85 MPH Speedo. 87 is the only years to have the Flat style Turbo Snowflake wheels.
1988
In 1988 The steering wheel was changed to a 4 spoke style, and the engine went to a serpentine Belt. 88 & 89 are very similar on the surface, if there are no rear seat shoulder belts then it should be an 88. In either Mid 88, or as an option, the Dished in High Tech Turbo Wheels were available on the Formula.
1989
In 89, the rear shoulder belts were introduced, and the 9th injector was removed from the Fuel Rail.
1990
1990 looks similar to the 87-89s, but has an airbag steering wheel.
1991 & 1992
The Firebird received a facelift, or change, it got the Banshee style front fascia similar to the early 4th generation Firebird front fascia. 1991 also got the flat style rear spoiler. 1991 and 1992 are very difficult to tell the difference without looking at the VIN. There are obviously differences, but a simple walk around my not be possible.
For more information on the specific nuances of each year please visit my History Pages.