Hey guys, I was always wondering, what's the difference between a non-WS6 base model 305 (non TPI) Trans Am and a base model V8 Firebird other than the ground effects and spoiler?

And I have a 1991 Trans Am WS6 convertible, I'm guessing that I have the same suspension as a 1991 Trans Am GTA because the GTAs came standard with the WS6 option right?

Thanks!

 

The biggest difference between the top of the line Firebird and the entry level Trans Am is TPI, body treatments (tinted grid tail lights, vented hood, aero spoiler), and 16" wheels. Those features weren't offered on the Firebird, and TBI wasn't offered on the T/A. Also the only suspension offered on the non-Trans Am Firebird in 91-92 is the FE1 package. F41 was standard on the Trans Am, with WS6/FE2 standard on the Formula and GTA, optional on the Trans Am.

For the later model years, WS6/FE2 are the codes for the level III suspension. Trans Am w/WS6, Formula, GTA, all have the FE2 and WS6 codes. So yeah, if you've got WS6 it's the same suspension as a Formula or GTA.

 

Thanks Drew! However I'm 99% sure that non-TPI Trans Ams existed. I could swear that I've seen a few. I know that a lot of Formulas were non TPI, in fact I have a friend with an 87 Formula that has the carb'd 305 engine (equivalent to the L03 offered in 88-92, right?). On the other hand, I'm pretty sure that TPI was standard on the GTAs. Maybe someone else can clear that up.

 

In 91-92 the only way to get a Trans Am with TBI was if it was destined for export. For the domestic market the entry level engine in the Trans Am was the LB9. In 88 and 89 you could get a Trans Am with TBI, but since you were asking about your car and a 91 GTA it sounded like you wanted to know about 91.

The 82-92 Trans Am engine break down...

LG4 82-87
LU5 82-84
L69 83-86
L03 88-89
LB9 85-92
L98 87-92
LC2 89

 

Drew, wasn't LB9 85-92?

 

Yep, typo.

 

Oh I see, yeah it looks like I was implying the 91s, but I meant all birds 85+. Oh well, but thanks for clearing this up for me! Because I was starting to think that a base TA was just a Firebird with ground effects and the tail lights.

 

The ground effects were offered on the base firebird starting in the late 80's... W68 was the RPO code. It came about kind of like the RS... There were some regional packages that mated the ground effects on the base Firebird to see how popular it would be. When GM figured out that it'd be extremely popular it became an option. By 1989 it was an option that could be ordered nationally. It's really obvious in in the 91-92's since most base Firebirds came with the gfx. That's part of the reason it's so common to see a base 91-92 Firebird without GFX labeled as a Formula by the owner.

The visual cues are easy to spot to tell a Firebird (non-W68) from a Formula, or a Firebird W68 from a Trans Am. The Formula and the Trans Am both had wrap around spoilers, and specific hoods (bulged hood on the Formula, vented hood on the T/A). The Formula and Trans Am also had 16" wheels, while the Firebird could only have 15's. The Trans Am also had the grid style tail lights.

There's also the vented fender question... Early Trans Am's have vented fenders, while Firebirds, Formulas, and GTAs always had solid fenders. But then later Trans Am's (91-92) didn't have the vents.

 

I was gonna add something, but after reading that, there isn't much left to say; Well done.