As you might have guessed i have a 88 IROC and I know a fair amount about 3rd gens, but I have never had a bird before and I've never really researched them much. Just a few questions for ya...

I just got a 91 Firebird and I can't find the RPO sticker. I looked in the center console, the spare tire well, and the storage comprtment in the trunk & no dice. Any other places I should look?

Also, how can I tell if this car is a formula, or what is the definition of a Formula. It has a 5.0 TPI motor, automatic, 16" rims, t-tops, and the highrise spoiler. The tail panel just says Pontiac and there is a sticker on the side of the hood bulge that says 5.0 FI. There is also a badge on the dash that says "performance suspension" I think, does that mean its a WS6? I didnt see any WS6 centercaps on it but i can't honestly rmember if there was caps on ther or not. Anyway, thanks for helping the Camaro guy expand his 3rd gen knowledge.

 

if it has a powerbulge hood and an earo spoiler (wraparound) and NO GFX, and it came from the factory that way it is most likley a formula. however, people pretty much think everything not a T/A is a formula. id you want to be sure you can always order your invoice from pontiac historical services www.PHS-online.com .then you will know for sure. you can also gain alot of info on formulas from http://www.3rdgenformula.com . have fun with your new bird.

 

Hey, I happen to own a 91 Bird. Check for the RPO sticker in the driver's side door *where it closes*. I dont believe the aero spoiler from the T/A was available on a Formula in 91, maybe someone added it? But you definetly dont have a base 'Bird because it wasnt available with TPI. The only V8 available in 91 for a base 'Bird is 305 TBI. To be sure, run your VIN through the decoder this site has. Lot cheaper than going through PHS... *its free*. And like Xophertony said, if it has the off-set hood bulge, called the power bulge, its a Formula.
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Btw let us know, and post some pics, 91-92 Formulas are killer looking... my neighbor has a red one.

 

Thanks for the info guys. From what I'm seeing, it looks like this is a Formula. This car is all stock. It does have the power bulge hood, the wrap around spoiler, and no GFX. I'll take a look at the door for the RPO sheet tomorrow when I tow it to my shop and have a good look at it. Thanks again for the info.

 

Sounds like all you need to do is decode the VIN number. That will distinguish if its a Firebird or a Trans Am. Then the 8th digit will indicate the engine, if it had TPI originally it's a Formula.

Always start with the VIN number, then the SPID if the VIN on the SPID matches the VIN on the cowl. The same goes for buildsheets, make sure the VIN number matches otherwise you don't know if the codes even apply to your car or if someone got a console at a junkyard. The VIN number on the cowl is pretty difficult to change, and is always the most likely to match the car.

The SPID was only ever installed in the console, and in the locking glovebox in the back. If it's anywhere else its there because someone moved it.

 

ALL 3rd gen formulas had the aero spoiler. take a look at www.3rdgenformula.com . okfoz from this site is the site administrator/author there. he knows almost too much about formulas. in fact he will probably chime in here pretty quick with a tidbit about how 2 formulas in 89 had no spoiler casue they ran out that week or somthing crazy like that

 

Where can I get a reproduction RPO sticker at and what info will they need to make one? Just the VIN or do they need a build sheet as well? I might have to take the car apart to find that.

 

the 91-92 forumlas also had a slightly different nose that the other 'birds if i remember correctly. The foglight area is larger.

https://www.thirdgen.org/forums/atta...4&d=1142102126

that pic shows the different formula front end.

 

Gotta be careful, that GFX-less nose is also available on the non-aero packaged 91-92 birds. Yes, you could get the 91-92 Firebirds without ground effects, it was an option.

Kevin D.

 

Ah, my bad, I checked the site and noticed the spoiler design changed in 91, and thats why I thought it was a different one from what the T/A's had.

 

Did the Formula come with a wonderbar or is that an IROC only part? If not, can I retrofit one? Any major differnces in the running gear or suspension between the birds and camaros? This car has a 10 bolt drum rear, any reason that my spare posi 9 bolt disc rear from my IROC wont work? They are both 2.77 I think.

I also did a through search of the car today and no SPID sticker anywhere. Can I get a new one from Pontiac Historic Services?

 

You can also go to a GM dealer's parts department with your VIN.Being a '91 they can enter it into computor and print you an RPO list for the car.This is usually a free,courtesy,service but then some will charge $5-$10.Now past a certain year they say it's not in the data base.I was told this by my local GM dealer(it's a Chevy,Pontiac,cadiallac,GMc truck)for my '83 Z28.They did print me one out for my '95 Jimmy.I haven't had time to check with another dealer as the next one is 40 miles away.

 

Run the VIN, the base model 'birds did not have the TPI motors, however the Formula's could have the TBI motor.

 

Did the Formula's have wonderbars?

 

Wonderbar was not offered on Firebirds

 

The Firebird lineup of cars did not recieve the wonderbars. Only the IROCs did.
But, you can install the stock IROC factory wonderbar onto your car.
The aftermarket wonderbars work the same as the factory stock ones, and the factory stock ones are cheaper. Either way, it is up to you.
The rear should work out for you, but you might need some other parts, like the proporchioning (sorry about the spelling) valve, and maybe the booster.

Have fun with your new toy,

George

 

- You pretty much nailed it on the head, THe Formula came with the 16" Rims, the Aero Spoiler, Buldge hood, no ground effects, & WS6, Its definately a Formula, All Base Firebirds & Formulas from 86 - 92 simply stated "Pontiac" between the tailights, right above the Text there should be a RED Bird, The Gold Bird & Text was used from 86-90.

- In this case YES it means WS6, As all Formulas got WS6 from 87-92.(Although the Badge is not a reliable means to determine WS6). The center caps SHOULD state "WS6 Pontiac Performance Suspension" Its possible that they were cracked & removed when the tires were changed.

Very True, I have seen a few of these with a V8 that someone bought "Formula" Decals for... OH:

You are correct, However id the car was equiped with the 1LE I believe it came with a Wonderbar Firebird or Camaro.

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The Engines for 1991:
RS - V6 & LO3
Firebird - V6 & LO3
Formula - LO3, LB9 & L98
Z28 - LB9 & L98
Trans Am - LB9 & L98
GTA - L98 & LB9