Hey guys im trying to figure out what gear ration my car has. I know in 91 the only gears available were the 2.73, 3.23, and 3.43 my car has a high top end which is 122 before the speed limiter kicks in. And it can burn tires when i want it to so it doesn't seem like I would have 2.73's. I replaced my center console with a new one. The old console that i ripped out didn't have the rpo sticker in it either. So is there anyway to figure out my gearing and options now. By the way its a 91 formula with a 305 TBI soon to be LT4 Hot Power. Can anyone help me with this stuff I need to know if I have to change out my gears before I start modding away on this thing.

 

Nope. Not in the VIN.

Take off the cover and look.

Have you changed the rear end fluid since you've had the car? I thought not. So while you're catchjng up on the overdue maintenance, make a point of looking at the gears.

The car almost certainly came with 2.73s if it's an auto or 3.08 or 3.23 if it's a stick. Of course, that may or may not have anything to do with what's in there now; and your speedo may or may not be anywhere near accurate if the rear has been altered or replaced.

 

depending on how nice your local dealer is, they should be able to find out the gearing based on the VIN, i called one (well two , but only one would run it for me) of the local dealers, and gave them my VIN, they looked up my car, and told me the gear ratio i had.

 

Check the glove box in the rear hatch for the RPO code sheet. Usually on the underside of the lid.

RBob.

 

I wouldn't screw with "codes", "tags", build sheets, dealers, historic services, or any of that. Nobody updates that stuff when they change the parts.

Take off the cover and look. You need to do it anyway. It's the only 100% sure way to get it right.