I have an 88 trans am with the lo3. it has large sway bars, and it came stock with 245/50 series. Is this car a ws6? Is there any other way to tell? The are no rpo codes or build sheets left.
Also, it has rear drum brakes. Is is possible to gave rear drums and posi? or is posi a disk only option?

 

i have noticed on some, maybe all ws6's, it will say high performance suspension on the passenger side dash.

 

What size wheels do you have? How many turns lock to lock to turn your tires/wheels? WS6 cars got the 2.25 ratio steering gears. Non-WS6 cars got 2.5 ratio. The performance suspension sign on the passenger side is not only for WS6. I think just about all cars after a certain year got that with the first level suspension upgrade. Which I think was Y41? Something like that.

If you have 16 inch wheels and a 2.25 ratio steering gear than you should have WS6.

 

Sounds like it is.

Disc brakes were an option that year.

 

If it came with 245's, I'm inclined to say its a WS6. All of my "non" WS6 cars came with 215's and my WS6 car had 245s.
Yes, you can get drums with a posi and WS6.