Here's something i read that might help. Also if i'm not mistaken you can call the any gm dealer and get a reprint of the RPO code label that would be on the truck lid of the car. Here's a link to how to read to RPO codes.
Buick Turbo Regal Option Codes (Regular Production Options - RPO)
1987 Buick Turbo Regal?
"At the risk of ruffling feathers of some, I'll try and clarify the "Turbo T" package as Buick marketed it in 1987. Despite Buick dropping the T-Type designation for 1987, all the cosmetic and suspension options common to the T-Type were made available for any 1987 Regal with the standard 3.8-Liter V6. They did this by offering a "T" Package (option code Y56). This "T" Package consisted of the Touring Suspension; Leather wrapped Sport Steering Wheel, Turbo aluminum wheels, Eagle GT Tires, Fast Ratio Power Steering, Gas Shocks, and "T" ornamentation. For those who also wanted the black trim from the previous T-Type model, Buick offered the Exterior Sport Package (option code WO2). The WO2 option was available on any Regal, regardless of the engine.
Now, if you wanted a Regal with a turbo engine, you ordered the "Turbo Package" (option LC2). This package automatically included the "T" package (but not the WO2 Package). What you ended up with was a Regal with the "Turbo" and "T" Packages. Many have chose to call these cars "Turbo T's". However, no where in Buick's literature was there ever any mention of the term "Turbo T" until Buick released Product Information Bulletin 87-031 on November 15, 1986 entitled "Regal WE4 Turbo "T" Package. This bulletin announced the release of the WE4 as a "Special Turbo T Package" and made numerous references to the term Turbo T as unique to the WE4. Here is a direct quote from this bulletin: "The WE4 Turbo 'T' Package will enable you to merchandise a car that is similar in appearance, and yet lighter in weight, than today's Grand National. This reduction in weight theoretically makes the Turbo T faster than a Grand National, and for a lower price."
So, a 1987 Turbo Regal, without the WE2, Grand National or WE4 Turbo T option packages, really had no unique name. It was merely a Regal with the Turbo Package or a Turbo Regal, if you will. Now, having said all that, it certainly is no great sin to call a Turbo Regal a "Turbo T" because it's convenient to do so. It's just not technically correct." --RK
- This text was taken from a post from Turbo Buick list member Ray Kammer on December 25, 1998. It is probably the best (long) explanation of the "T" signification.