okfoz

I know that there have been several discussions about The T-tops and 350 cars and for a brief time I was under the delusion that they did not exist.

Well we all know they exist, I own one, Scott Moyer owns one, heck there are alot of them out there... In 1987 & 1988 they are far and few between, they are not "Rare" but unusual. I have yet to see an 87 or 88 Firebird with the 350 and T-tops however. 1989 they seemed to have opened the floodgates and they made tons of them, something like 1030 Formula 350 T-top cars out there alone... Then in 1990 they went extinct again... But in 1991 Pontiac was blessed with the Formula 350 with T-tops, this would continue through 1992...

At this point you probably need to read some other stuff to follow me beyond here

First Read the article by Frankie Rider on his excellent web site: http://www.gtasourcepage.com/newdevelopment.html
Then if you want to follow a thread discussion you can find it here: https://www.thirdgen.org/forums/hist...-ers-here.html

In the article you read that the GTA was a heavy, loaded out car, To lighten the car they did things like changing to the cross-laced rims. It was not a styling thing it was a weight thing...

So how does this relate to T-top 350 cars?
First we have to undertand that T-top cars are HEAVIER than Hard top cars, its a matter of the glass, and the additional weight from some minor structural changes, I have been told that T-top cars even have a slightly thicker floor pan to help strenghten the cars.

I was told by someone who works for GM that the reason for T-top 350 cars being unusual was because of the CAFE requirements, if they offered the T-tops on these cars it would lower the overall CAFE for the brand...

This got me thinking... Why then in 1989 was the 350 & T-top such a common combo? Its simple, by the end of the life cycle in 1989 of the MAF TPI system they had refined them to get slightly better milage. My 350 vert gets an honest 25mpg highway. The EPA numbers may not show up much different than 1988, but its probably just enough to let them pass.

Then I started thinking about why Pontiac be allowed a T-top 350 car in 1991 & 1992 but not Chevrolet???
Here are some Facts:
1) The formula is naturally lighter than the Trans am and the GTA, It has no ground effects, less available options, etc.
2) The Cross laced wheels are lighter than the standard Formula wheel, read the article again if you missed it the first time.
3) The G92 was NA on the camaro when equiped with T-tops
4) The cold air intake system of the Firebird is far inferior to the Camaro, the camaro boasted about 5 to 10 HP because of this.
5) The formula in 1991 & 1992 is slightly lighter than the 1990 model because of the spoiler alone. The Rubber spoiler is a heavy Son of a gun on the other hand the plastic spoiler in 1991 very light.

I have read and even stated from time to time that the Torque of the 350 may have overwhelmed the T-top cars and therefore been a partial reason for the lack of the combo... I now believe that this may be wrong. The 350's torque is not significantly different than the torque from a LB9/M5, when equiped with the 3.45 or 3.42 gear.

My bet, would be that Pontiac wanted to put T-tops on all of their Firebird models, but because of the added weight the cars would have crossed that infamous barrier into Gass-guzzeler land. Since the Formula 350 was only available with T-tops and the light weight rims it may be that the car was just below the threshold and was the only car to get the EPS's blessing and not cross the barrier. THis is probably true for the Camaro as well, and why they were NA with T-tops and the 350 in 91 & 92.

This is probably also true for the Convertibles and why Pontiac was not in the game directly at first. Since the cars probably did not need to have EPA certification when an aftermarket company like ASC did the convertible conversion, and production was below 500, they flew under the radar. Also consider that the Firebird Trans Am is slightly heavier than its Camaro Z28 brother, when the top is cut off and SFC's are added it may cross that line into the Gass-guzzler territory. By 1991 they had made a lot of improvements to the TPI engine, and the milage was probably just good enough to not have the cars cross that line... Again it would make sence that the reason for no 350 was fuel milage, not body torque.

In the literature I have there is no provision for a performance gear ratio on the Trans Am convertible. There may be some cars out there with the option, but its not on the order sheets... In the 1992 Pontiac Dealer brochure it states that the "Performance enhancement group" was Not available on the Convertible.

With all of that said... Why no T-tops with the 350 in some years, on some models, my bet is Gas milage...

Why no convertible the 350 or with the performance gear ratio in 1991 & 1992? Gas milage and the Gass-guzzler barrier created by the good ole US Government.

John

labrat

Well it makes sense. The Feds really did control what the factories could do with the cars(and still do), the 85 mph speedo comes to mind!

I guess the only way to know for sure is find someone that worked at GM back then and dealt with the regualtions regarding weight, and mileage.

cdartz

Well your hypothesis makes perfect sense to me. I doubt however that we will ever truly get an accurate answer. At this point it's all hearsay.

Drew

iTrader: (58)

It sounds logical, but like artz is saying, it's open to conjecture and debate only. Also, even though there are no numbers for combinations, and we'll never know how many cars had L98 and CC1, there were MANY built. It's not rare at all on the Camaro from 87-89 at least. I've also seen several birds with the L98 and ttops. The EPA gas mileage estimates are also very close across the entire line, the V6 wasn't very far off from the L98 most of the time.

It's one of those things that will never be fully clarified, but honestly I wouldn't consider L98 + CC1 rare at all. There are pro's/con's for both the hardtop and the ttop, it all comes down to personal preference. It's not like a L98/CC1 car is worth twice what a LB9/CC1 car is worth, or L98/hardtop.

rwdtech

i doubt the floorpans are thicker for t-top cars. you all know how GM is, like they care....

ershealy

When were the Lexan T-tops available? They were a good bit lighter than glass. Did the 350 T-top combo disappear when the Lexan tops were discontinued?

Drew

iTrader: (58)

Lexan came and went back and forth a few times between 88-92. Between GM deciding to recall them or replace them under warranty with glass, and alternating back and forth, there's no set rule that I've ever seen.

okfoz

I was always under the impression that the Lexan tops appeared in 1989. Someone I thought had an OE acrylic top box that had 1989-1991 on it... could be wrong.

Drew,
I know that in 1989 that the T-tops & L98 were common, and in 1987 & 1988 there were alot of camaros with them. Have you ever seen an 87 or 88 Firebird with the 350 & T-tops? I have not.

Also, I thought the lexan tops were "CC3" instead of CC1...

John

FrankieRider2

John, I'm not Drew.... but in all the years I've been traveling to shows and getting submitted photos for The Source Page I've only seen one such Pontiac F-car.

There used to be a fellow from Ohio named Brad Duff who attended the Trans Am Nationals every year in a Flame Red '87 GTA that had the paddle mirrors on it. It was the only car I've seen before '89 that had both the B2L and CC1 RPO codes together.

okfoz

Frankie,
Your as good as or better than any one else for info...

I wonder if the reason was it was an early production car, and thats why it had the T-tops & B2L... IIRC there was somone on the boards with an 87 Blue/silver Trans Am with the combo, but without seeing the SPID sheet I was never 100%...

thanks

John

92GTA

iTrader: (11)

Just to note, my 92 GTA has factory original Lexan tops and CC1. My 91 GTA had factory original glass tops and also had CC1. I don't think I've ever seen CC3

Also I can vouch that while I had TransAmGTA.com running I came across a legit 1988 White GTA that had L98/CC1. It of course had glass tops. I also wanna say I've seen a 90 but I just can't remember anymore. the white '88 stands out because it was actually being sold at a local car lot in Lake Isabella CA around 1998/1999 and I test drove it to buy before finding my 92 GTA in 2000 but didn't because it was beat

I've seen only 2 92 formys with the L98/CC1 combo and yeah, a ton of 91's over the last 8-9 years I've been paying attention.

okfoz

Another note of interest is the 1987 SUbwoofer option that was NA on the GTA... Another weight saving thing? I wonder.

John

Drew

iTrader: (58)

Is there anything in the Firebird promo literature from 87-88 that suggests CC1 wasn't available with L98? If it weren't available it'd say so, otherwise they would have had some unhappy customers.

I've never seen anything suggesting that it's a rare combo so I never really kept track. When I was looking for the car back in the mid-late 90's I looked at more thirdgens then I could count on used carlots, private owners, junkyards, etc and seeing a L98/ttop Firebird wasn't that unusual. Camaros were more common, and most of the Camaros I remember looking at were ttop cars.

okfoz

Actually T-tops & the B2L options in 1987 & 88 are NA:
- on the Pontiac Dealer Order work Sheet "N.A. w/B2L Engine - N.A. w/LB9 Engine w/Auto Trans w/J65 Four Wheel Dis brakes on Formula." (Figure that one out).

To answer your question, No there is nothing in the PROMO lit to suggest as such, however the delaer order worksheets DO say that its NA. I have spoken to people at car shows who have owned their car since new, and they tried to order the 350/T-top combo in 87 & 88 and were not able to. Its not that they are not out there they are very rare as a combo for these two years.

John

Drew

iTrader: (58)

Could also be a mid-year change in thinking. GM likes to change the rule, midstream. We'll just have to agree to disagree on the 'rare'. I personally feel that the term 'rare' doesn't really apply to these cars. The presence or lack of ttops doesn't make or break the car in my opinion, and I can't see a disproportionate skewing of the price tag due to that kind of variance. Especially at this point in the game where ttop cars are likely going to be far more hammered and unstable then comparable hardtops.

FrankieRider2

Drew, I think you and John could both be correct on both your points. John about the weight restrictions and you about the mid-year change(s).

The UQ7 subwoofer option would have added some poundage to the GTA, but why it was available only on the 5.0/5-speed cars only is anybody's guess. But apparently weight was a big issue on the GTA.

As for the 350/T-top deal, the CDBs from those years could provide some sort of answer. I have CDB 90-F-2 dated August 29, 1989 that is labeled "Firebird Hatch Roof Restriction"; it states that no B2L-equipped Firebird will be built with the hatch roof. It also states that "UPC LB9 is now available on the GTA with UPC MXO Automatic Transmission". This "allows for a build combination of GTA, Automatic Transmission, and Hatch Roof".

It also states the the next printing of the Firebird Car Order Worksheet will reflect the change. Not always, as I've found messing with these CDBs. Lou Wassel has told me the entire ordering system was filled with possibilites for error.

I also have the CDBs for 1992 and there is no mention of them about the Formula/B2L/CC1 availability. It must be somewhere in the 1991 set, which I do not currently possess.

okfoz

Frankie, Actually the things that were NA on the GTA & Trans Am with the 350 OR the LB9-A4 in 87:
D42 - Cargo Security Screen
UQ7 - Radio Speaker Subwoofer

It looks like it was weight savings...

ACTUALLY, this may shed some light on the fact that in 1987 the Camaro Vert when equiped with the LB9 was only available with the Manual Transmission...

John

Finntroll

"1030 Formula 350 T-top cars out there alone... " I'd just like to state that considering the production numbers of firebirds in 1989 which is something around 16,670 according to this site that 1030 350 t-top formula's is not a lot of firebirds with that option. I'd probably say that they are the rare"er" firebirds for 89 out there. 1030 cars out of close to 17,000 made is a small handful also taking into consideration ones that have been scrapped over the years. Fact is, there are more Turbo Trans Am's than there are 350 t-top formula's, and TTA's are considered a rare collecters item. I think we should cling to our 350 t-top firebirds, I think they will hold quite a value in the later years. Also about the t-tops being heavier, many of the t-tops were plastic and not glass though many of the plastic ones ended up warping and being shot and got replaced by glass under warranty. Just some food for thought. Hit me back. - Edited to say that I don't have a deep knowledge of these cars i'm just looking at numbers and using simple logic, i'm not 3rd gen wiz obviously by my own post.

okfoz

In the Grand scheme of things, I think your right. THey are more or less "uncommon" Albiet "Rare" I would think are cars which there were less than a few hundred or even less than 100.

When you consider that 42 were for sure made into convertibles, that takes the number just below 1000. The TOTAL number of 350 cars in 1989 was 13,041 cars with the 350.

When you consider that there were close to 54,754 Formulas made from 87-92, and around a total of 800,000 Firebirds total from 82-92, I would argue that they are more rare than most.

Keep in mind that "Rare" =/ Valuable Just because there was only a few of them made, does not mean that people will want them. The I4 F-body car is in the book of "Cars you love to have" Fortunately your on the other endo of the spectrum and the value will be there in the future.

John

Hylton

I just want to clear something up - G92 IROC 'verts were available in '88. I own one of them.

okfoz

Prior to aroun 1990 or 1991 that may be completely possible... Some where along the line that changed however, for one reason or another the G92 became NA for the verts & T-top cars, again I suspect due to the Added weight of the equipment that came with the G92, IE the Oil cooler, Dual cats (starting in 1989) etc... I think also thats why alot of our cars have the Aluminum driveshaft, it was to save weight to keep it below a mysterios number to avoid the Gas guzzler taxes...

John

Drew

iTrader: (58)

It's important to look at the big picture... How can you consider ttops rare (regardless of combinations) when so many 82-92 F-bodies had them? I haven't got any Firebird numbers handy but here are the CC1 numbers for 82-92 on the Camaro.
82 53,338
83 51,471
84 90,278
85 63,543
86 91,089
87 59,600
88 41,005
89 44,595
90 12,476
91 38,836
92 28,003
That's 574,234 Camaro's with ttops, not including C&C cars, other aftermarket conversions, etc... With what is probably a million ttop fbodies produced, I can't consider that rare. If you want to break it down by combinations to make it rare, you can do that with any of the options. Just about any thirdgen can be considered rare when you factor in all the different options that were available.

92GTA

iTrader: (11)

Well does anyone have a listings of all the advertised curb weights for all the different models and years? Then we can atleast speculate a little bit better on this whole subject. I'd think information like that would help us get closer to disprooving it or coming to the conclusion that it may be a viable excuse. Maybe make a post asking people to tell us what their door sticker says the curb weight is.

Then there is tracking down D.O.T. of whatever regulations saying a vehicle of X weight with an EPA milage of X and whatever....

There has to be real factual info that's obtainable, otherwise the whole concept goes out the windows because no auto company is going to waste payroll and R&D $'s on researching stuff like that in an effort to be compliant with a regulation that doesn't exist you know...

Abubaca

iTrader: (3)

Well said.

....rare, valuable, uncommon, it's all relative. I think specific options are what makes a car valuable, not how "rare" it is. Get down to 4 or 5 left, then "maybe" rare starts to add serious dollars, but until then, it's just another car. They hold sentimental value to us, but that's about it.

Finntroll

Nobody ever said Ttops were rare. For 89 the Firebird Formula 350's with the Ttops option was a bit rare with the engine and top combo, thats all i'm saying. Then you break it down into more and more power options and that makes it even more so. My firebird has tons of power options in the car excluding electric seats and belts. From what i've read it has just about everything else or had at one point (3rd owner so some things don't work to great atm). Ttops certainly aren't rare, especially in the 3rd gen. However alot of people when looking for older cars come across what they want and it has ttops it has kind of a "it has ttops to!" kind of effect. People like ttops, thats why they made a ton of them. While it dosen't make or break the selling price, it certainly is a good selling point to many. I'd personally like to say that both of my cars have ttops and they are more of a hassle than anything. They leak, they crack, they rattle, but when they are out its nice and I wouldn't give either up.

okfoz

NOw that we have gotten completely off course with the topic of discussion. The PURPOSE of this thread is not to discuss how rare a car is with a 350 & T-tops, Although it does play into the discussion, the main point is that the reason why many people were turned away at the dealership when they tried to order a car with the combo was to do with the Added weight of the tops.

Lets keep it on topic. please.

John

FrankieRider2

John, I got an email from Lou Wassel today and this is what he had to say about the decision to not offer T-tops on the 5.7 cars:

"It was strictly a matter of 'gas guzzler' certifiication because of the added weight. Nothing more. Not sure how the ones you're describing got built."

Same deal for the UQ7 and D42 options as well in '87.

As for the 1991-92 5.7 Formula with the T-tops, he said the combination of the lightest body (Formula) and the lightest wheels (PW7) made those cars possible.

TTOP350

iTrader: (8)

I have a 89 formula with TTOPs and a 350.. i bought it from the orginal owner. It had the R6P N10 and a few other goodies.. steel driveshaft and spare. It also has glass tops...
most 89 formula 350s around where I live have TTOPs
one crazy thing I found during the first repaint was the molded air extractor on the hood was painted red under the factory black paint!!!! I have talked with the 1st owner and he never had any paint work done to the car before I got it !!!

Oh and my cuz just bought a blue 92 formula350 with TTOPs it has a steel shaft,N10,R6P the painted black aluminum spare and crosslace wheels.. best part is he paid 2,500 for it

AmorgetRS

iTrader: (6)

So that basically 100% confirms okfoz's theory!

okfoz

Frankie,
1) Does Lou happen to know at what point a car becomes a "Gas Guzzler" (for the 80s)? IE what is the Weight vs fuel milage, or is it fuel milage only?

2) Since that is true for the 350 & T-top cars then I would assume that would be the chief reason for the Convertibles as well?

3) Why in 1989 were there so many F-cars with T-tops & the 350, was it an oversight or did something change in 89 that allowed it. I know they cheepend the cars up slightly, like not painting the lower trim pieces under the front facia on the Firebird & Formula, not painting the firewall between the Engine bay and windshield Black, were there other factors that allowed it?

4) To add to this... I would assume that would also be the reason for the Aluminum spare tire in the Trans Am's & GTA.

GTA Jim

I'm wondering if anyone knows where these 'extra braces' are in T-top cars? I've heard about it, but haven't been able to confirm it anywhere..

I've been to lots of boneyards where I've examined f-bodies in various states of disassembly. I've never been able to see any difference between T-top and regular cars. FWIW, The rear hatches of ALL the late 80's F-bodies I've managed to see are stamped with the tie down points for the T-Top bag whether they came with T-tops or not. If they do this, I'm sure the 'special' bracing would be installed in all bodies, not just the T-Top cars. It would cost more to build two separate frames.

I have a publication from the Motor Vehicle Manufacturer's Association that has the specs of 1990 Firebirds. The information was submitted by GM. (See photo of cover below).

They list the CC1 hatch roof as adding 12.8 Lbs to the front axle and 21.1 Lbs to the rear axle for a total extra weight of 33.9 Lbs. Considering the glass alone is pretty heavy, there isn't much weight left to account for much 'special bracing'.

On the topic of weight... I just can't see 33 lbs pushing a car into the 'gas guzzler' range. It's not a lot.


Here's the publication:

AmorgetRS

iTrader: (6)

I don't think the lightweight crosslace rims saved much more (if any) then that. These cars were right on the edge from everything Lou has said.

GTA Jim

Going further into the specs, I see that the LB9 adds 154.8 lbs over the base V6 car and the L98 adds 164.9 lbs to the total car weight over the base V6.

So a 350 with T-tops only weighs 10.1 lbs more than a 305 with T-tops. They sure must have been cutting it fine

okfoz

Jim,
If you read above, the GTA & Trans Am in 1987 were NA with the Subwoofer system or the Rear security shade, when equiped with the LB9 or L98 with the Automatic trans..

As for the weight differential of 10.1 pounds, keep in mind that the L98 came with the Oil cooler, Ltd slip axel, and the disc brakes. I do not know if the disc brakes were heavier or ligher than drums, I would suspect lighter than drums, but the Ltd slip is definately slightly heavier than the normal open rear end.

I found this interesting:
From 1987 thru 1990 the 2BL package remained the same:
MXO - Automatic Trnas
G80 - Ltd slip axel
KC4 - Engine oil cooler
J65 - 4 wheel disc brakes
WS6 - PErformance suspension

Interestinly in 1991 the 2BL package was
MXO - Automatic Trnas
G80 - Ltd slip axel
QLC - P245/50ZR16 BSW tires
RP6 PErformance enhancement group
N10 - Dual convertor exhaust
FRONT DISC - REAR DRUM & 3.23 rear axel
WS6 - PErformance suspension
NA w/CC1 Hatch roof

In 1992 however
MXO - Automatic Trnas
G80 - Ltd slip axel
QLC - P245/50ZR16 BSW tires
RP6 PErformance enhancement group
N10 - Dual convertor exhaust
J65 - 4 wheel disc brakes
WS6 - PErformance suspension
NA w/CC1 Hatch roof Exc on FOrmula w/PW7 Wheels

Midwest Muscle

This is an interesting discussion. The '89 IROC I ordered new when I lived in Germany was a 350 T-Top car. I just figured most everyone ordered them that way, unless of course you preferred shifting gears instead of putting it in "D".

GTA Jim

That's true. The 10 Lb difference is for the motor only. With the L98 you did get other 'stuff'

I guess the only way to tell would be to actually weigh cars that were identically equipped. One with an LB9 and another with the L98 plus the extra things that came with that engine.

Drew

iTrader: (58)

Now technically, 91 L98 birds were supposed to have rear discs required. The general explanation for the rear drum L98 birds is a shortage of PBR parts. All the printed information I have for 91 specifies 4wd brakes.

FrankieRider2

The documentation I have supports John's assertion on this topic.... the order sheet for 1991 specifies the R6P group for all B2L Firebirds for 1991. This option group for 1991 included the disc-drum brake set-up. The sheet also specifies rear drum brakes on all LB9 Formulas and GTAs with the 3.45 rear axle and 5-speed transmission.

The order sheet I have is dated 07-90 and is the Fourth Printing. I do not presently have the CDBs for 1991 that might reveal any dates that brake component changes were implemented during the model year. Also, any later printings of the order sheet might have changes as well.

But two of the five 1991 tests I have denote the test GTA as having the 350 engine and rear drum brakes.... including the SLP-equipped test car sampled by Motor Trend. Even with the consideration of publication lead times, both articles are from late in the model years as well.... August and September 1991.

rideon1200

I have a 1987 formula firebird with t tops and a 350. Put the 350 in last week 1

G8T8A

One thing to add to the mix is the fact the wheels are unsprung weight. The non-crosslace wheels are like heavier flywheels that the engine had to spin up to speed.

AmorgetRS

iTrader: (6)

All true, but I really doubt that CAFE standard took that into account

FrankieRider2

John, I just heard from Lou again this AM and this is what he said about the weight issue....

<< Yes, the fuel economy issue required an annual all-day meeting to go through all the mass reduction possibilities. It was usually within a couple of kg. >>

That's pretty tight....

xcalibur

[quote=GTA Jim;3327675]That's true. The 10 Lb difference is for the motor only. With the L98 you did get other 'stuff'

I doubt that the 350 motor itself is 10# heavier than the 305, since they are both made from the same block. With a bigger bore, or shorter rods,
shouldn't the 350 logically be lighter ?
The 5.1# difference (350 being 164.6# vs 305 being 159.8#, when compared to the V6's wt), is probably just from the oil cooler req'd for the 350. The addition of a stock Al head could probably skew the wt either way.

xcalibur

[quote=xcalibur;4867330]

okfoz

They used Aluminum heads, Aluminum Block, etc in almost all cases has used to reduce weight... Interestingly There is actually a decrease in power from the use of identical Aluminum castings over the steel castings. However, you gain more from the loss of the weight than the loss in HP. So it is usually a wash.

CI heads are heavy, AL heads are about half the weight IIRC.

lotpowe

My 1987 formula 350 has the rear security shade. Havent checked the rpo yet im at work but will later.

okfoz

The security shade and the sub-woofer was available on the Formula in 1987 with the 350.... It was only the TA and GTA that they were NA with the 350, unless you bought your car in Canada, then you could get T-tops, sub-woofer, shade etc...

lotpowe

got ya

GTA50

And to think that I passed up buying a '87 GTA with 350/T-tops - yes I verified the SPID!!!! Price - $750

1991z28........

I have a 1991 z28 5.7 with t-tops. 8th digit on vin is an 8, and 5.7 is engraved on the engine block. However on the t-tops they have a stamp that says c&c (cars and concepts). So these t-tops were after market?