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History / OriginalityGot a question about 1982-1992 Camaro or Firebird history? Have a question about original parts, options, RPO codes, when something was available, or how to document your car? Those questions, answers, and much more!
Please excuse me if I am posting in the wrong area...haven't really posted anything before. In any case, I have been a thirdgen fan and owner since 1995. I have primarily had the IROC-Z variations..1986, 1988, another 1988, 1987, and my last one was a 1989 that I restored and kept for 13 years. Loved that car. However, kids college expenses got out of hand and I had to sell it about 2 years back. Was a G92 5 speed TPI with a few performance mods including a Zex kit. Black on charcoal..pretty much my dream car. Fast forward to now...was going through F body withdrawal and been looking hard for my next project. Turns out Iroc's are too expensive now..unless they are trashed or not stock (A/C ripped out, carbed, rust bucket..etc). I like a mostly stock vehicle. I was looking at Firebirds/Trans Ams..it seems there are more out there in mostly stock form at a reasonable price. I found a particular 1990 Formula with a 5 speed and T tops, but the ad had little description and few pictures..none of under the hood, and the guy really didn't want to answer too many questions..so I figured it was a TBI because it had T tops, and probably had the lame highway peg-leg rear. My 89 G92 Iroc was a hard top...and I don't remember seeing any (89-92) G92 with N10 with t-top. My understanding with the Camaro was if you got the G92 with N10, you were getting a hard top no matter the engine size. However, when I went to go look at the Formula..it had a TPI 305, 5 speed, T tops (CC1), and dual cat configuration (cats replaced with two straight pipes..saves me the trouble..lol!!). The RPO sticker was missing..checked both spots. I went to Compnine website and entered VIN, paid 5 bucks. Indeed, it did come up as a CC1, N10, GU6, G80, J65, LB9, MK6, MM5, N10, and WS6.. I guess Pontiac doesn't use a G92 code?? Maybe that's specific to Chevy. Sorry for the long-winded post..but the short of it is that I went back and bought it. Needs quite a bit of work..but it runs good, and the floor pans are in unbelievable shape, very solid. The lower radiator support only has a bit of surface rust in one spot, and the battery tray is actually not completely rotted. What I am looking to find out is if this is a bit of a rarity (certainly not 1LE rare..lol) with this combination? Anyone else on here have one of these? I know there have to be some..But was it true that Chevy only offered G92/N10 with hard-tops, and maybe Pontiac just did their own thing? I will try to post some pics...of the Formula, as well as my departed Iroc...
BTW, according to Compnine they show 353 - 1990 Formulas with the LB9/MM5 in their database. It shows all of them had N10 option code. Of the 353, 247 of them had the CC1.
It should be noted that Compnine's figures aren't 100%. GM did not keep track of options on top of options and their records are also incomplete. So that means 3rd party sources won't have 100% accurate figures if the source didn't. There are some cases where it's believed to be fairly accurate than other cases.
I appreciate the info..I knew there would be some answers here. The thing that threw me off was the T-tops..Coming from the Iroc side of things, I never saw an N10 car with T-tops. I suppose that Pontiac Memo would force that combination if the customer wanted T tops w/5sp and TPI. At 247 produced..I am feeling pretty good though. I am not sure the guy knew what he had..odometer reads 87k miles (might be true, but i know these clusters get swapped)..Runs and shifts well, no smoke at start up (all my Irocs needed valve seals). I guess for $2k I got a decent deal. On to my parts quest. Carpet on the way..looking for dash pad, console lid..just sayin..I know there is another posting area for that. Does anyone know if the Hawks/Repro 91/92 TA rear wing/spoiler will fit a 1990 Formula? The OE one is a bit shot, and I like the look of the 91/92 style. I could always get a CHMSL for the inside rear glass, so not worried about that..
I appreciate the info..I knew there would be some answers here. The thing that threw me off was the T-tops..Coming from the Iroc side of things, I never saw an N10 car with T-tops. I suppose that Pontiac Memo would force that combination if the customer wanted T tops w/5sp and TPI. At 247 produced..I am feeling pretty good though. I am not sure the guy knew what he had..odometer reads 87k miles (might be true, but i know these clusters get swapped)..Runs and shifts well, no smoke at start up (all my Irocs needed valve seals). I guess for $2k I got a decent deal. On to my parts quest. Carpet on the way..looking for dash pad, console lid..just sayin..I know there is another posting area for that. Does anyone know if the Hawks/Repro 91/92 TA rear wing/spoiler will fit a 1990 Formula? The OE one is a bit shot, and I like the look of the 91/92 style. I could always get a CHMSL for the inside rear glass, so not worried about that..
$2000??? That's an excellent deal! Based on the condition of that car, specifically the seats and steering wheel, I'd put trust in that 87K being accurate. Looks like you scored a home run.
As for the hatch, I can tell you for sure that the 91-92 spoiler won't mount to your glass, but I can't confirm the deck lid itself. If I recall correctly, there are different mounting holes on the 80's cars vs the 91-92, so you'll likely need a new hatch.
The 30 second answer on G92 on later Firebirds is that Pontiac usually used R6P instead of G92. As always G92 means the car has an optional "performance gear ratio". In most cases on late TPI Firebirds, the gear ratio is selected automatically based on the engine/transmission choice, so there's no need for the G92 code to appear. Even R6P was only used for a short period of time, ex. 90-91, since it's largely redundant.
Great stuff everyone...thanks alot. As far as the rear spoiler goes...if that is the case for fitment (swapping the hatch for 91/92 style), I will probably just stick with the style that fits...I started disassembling the interior yesterday (I mean..who gets excited about that..lol..I do) to get it ready for the new carpet I ordered from RA. It was only a couple years ago I sold my 89 Iroc, but man..it was like not having my right arm. So happy to be working on a thirdgen again!! I am just glad the guys ad for the car was so vague...otherwise, I probably would have been beaten to the punch. Part of the reason I think I got it cheap was that the guy had to use starting fluid to initially start car..but then it would start/run all day. Fortunately..been there, done that...figured it out in less than a half hour. I hooked up my Diacom to it (by the way..initially..it did not link. FYI..Figured out the cable for 86-89 TPI, which is what I always used..7165 comp..has a built in resistor for those applications. Duh..the cable is labeled "86-89 TPI"..lol!! The other cable, which I never used before, was fortunately still in the Diacom box..been sitting in there for 20 years! Linked right up to the 7730!) Anyhow, everything was reading with key on/engine off..like CT, TPS, IAC etc...so ECM power good..except during crank, no rpm. Eventually, after some time, even without starting fluid..the car did start as soon as ref pulse/RPM starting showing. No reference pulse..tested AC output on pickup coil..quite low. Could be the pickup coil..could be the magnet (distributor). Threw in a Cardone dist. with all new stuff (replaced the IM with a Delco I had from a prior ignition saga)..starts up immediately !! Just really happy to be back into this stuff..!!
Project update..I usually do these cars in three stages..Interior, mechanical, body/paint. I was finally able to put a decent amount of time into the interior over the Summer/Fall, but with my busy work season coming I am putting it away until Spring. Interior just about done...some photos..did just about everything. Steering column was pretty shot, so did a 1989 no airbag wheel, no Vats (a couple of 5 cent resistors, no airbag light...no VATS issues)..4th gen seats, pro 5.0, headliner, T-top seals, carpet, etc..etc..I have new visors on order..and that's it. Not doing any audio stuff until after mechanical stuff (brakes, suspension, exhaust, some minor engine tweaks/service). I couldn't resist the 91-92 spoiler..so yes, going with it...I have already made provisions to mount it. The door panels were originally fitted with those god-awful plastic cup holder/pockets..but the door panels were in nice shape so I wanted to keep them..so I used the older style flat vinyl pockets in their place. However, I had to offset them back a bit to completely cover the holes left by the original plastic pockets.
Can't wait until Spring when I can make it a driver!!
Three!! nice..I get it...They are fun to drive..theraputic for me. I know the T5 has a poor reputation...but if you don't shift it like an a-hole they hold up pretty well. I ran a 125 shot with my 89..while I seldomly sprayed, when I did...it took it like a champ. I did upgrade the clutch..but thats it. Can't wait to get this on the road..
Three!! nice..I get it...They are fun to drive..theraputic for me. I know the T5 has a poor reputation...but if you don't shift it like an a-hole they hold up pretty well. I ran a 125 shot with my 89..while I seldomly sprayed, when I did...it took it like a champ. I did upgrade the clutch..but thats it. Can't wait to get this on the road..
Dont underestimate the T5 like most people do. I ran a mild ZZ4 with a WC T5 in my 3400lb 84 15th Anniversary and went 12.teens-12.20s with it. Launched wide open at 3500 on DRs, and powershifted every gear at 6000. Ran a Centerforce DF and a Pro 5.0 shifter. Ran the car like that for years without a single issue. Many Fox guys are still running deep in the 11s with T5s.
09-20-2020, 07:56 PM
!! Just really happy to be back into this stuff..!! 
