Ok Ive been searching for a long time now to find out what stock gear that 5spd equipped 89 formulas came with, so if any one knows drop me a line thanks.

 

https://www.thirdgen.org/newdesign/tech/techdb.shtml

 

what is the difference between the standard t-5 and the opt. G92 t-5?

 

if you had a 5 speed car and it being a 89 you most likely have a borg warner rear and 3.45 gears. if you have a 10 bolt you will have 3.42s.
to tell if you have a borg rear creep under the car and if you have a plug in the diff cover and the bottom of the center section will have the borg warner insignia.
the borg 3.45 gears are hard to find. cocaclakid recently mentioned he has hte info to get replacement gears from austrialia.
Miles "might" have a set recently come thru. he sells all the stuff for 9 bolts. also if you pull the diff cover and roll the ring gear around that will tell you the ratio as well. if you still have your RPO sticker in your console that will tell you also with the GM3 code for 3.45s.
GU6 is the 3.42 code.

 

G92 is a camaro option. therer was a discussion about this in the history section. OKofOZ had alot of info on this.

 

My 89 TA came with a 3.08 rear gear. I believe that there were also 3.43 10 bolts available.