89 convertable Iroc-z collectors sieres
89 convertable Iroc-z collectors sieres
Hi everyone this is my first time posting and I have a question that's been stumping me for awhile, Has anyone heard of a 1989 Iroc-z collectors seires, a friend of my brothers bought a 89 Iroc years ago and inside and out, even under the Iroc logos on the door and on the iroc centar caps on the the rims say collector sieres. It's a convertable and it has a 350 in it but the vin # says it should be a 305, the vin has a 3 in it to say it is a original convertable. The guy he bought it off of, said that it is a very rare car, he also bought it in the U.S.A ( we live in Canada)He's had it appraised and the appraiser told him it maybe 1 of only 3 like it in Canada. Does anyone know any info. on theses Iroc's
Member
Joined: Feb 2008
Posts: 348
Likes: 0
From: Pensacola, Florida
Car: 88 IROC Z Vert CZA3
Engine: LB9 5.0 tpi
Transmission: MM5 5 spd
Axle/Gears: G92 Performance
Re: 89 convertable Iroc-z collectors sieres
Never heard of it but I learn something new often. As for the 350 it was never offered by GM on a vert. ASC did however "produce" L98 verts but you will never find a VIN with a 3 as the 6th number (vert) & an 8 (L98) as the 8th number. Sure would like to see some pics of the ride and the graphics.
Supreme Member
Joined: Jul 2006
Posts: 1,672
Likes: 4
From: Killam, AB
Car: 1989 IrocZ Convertible
Engine: 305 TPI
Transmission: T5 - 5 Speed Standard
Axle/Gears: 3.08
Re: 89 convertable Iroc-z collectors sieres
Sounds to me like it was a typical '89 IrocZ vert with an LB9 305. Then either because the L98 & LB9 look identical, somebody lied or is mistaken and called it a 350 or a 350 might have actually been swapped in. Then just add some graphix plus a good story and presto . . . a rare car.
Much more information, or better yet, actual documantation (even pics wouldn't prove anything) would be needed. Without that, all he had was a good story.
Chances are the previous owner might have been trying to score a good $ale. For me, if he didn't provide any verifiable documentation, then it means nothing and I would never buy one based only on that.
PS; welcome aboard!!!!
Much more information, or better yet, actual documantation (even pics wouldn't prove anything) would be needed. Without that, all he had was a good story.
Chances are the previous owner might have been trying to score a good $ale. For me, if he didn't provide any verifiable documentation, then it means nothing and I would never buy one based only on that.
PS; welcome aboard!!!!
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Joined: Mar 2001
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From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
Re: 89 convertable Iroc-z collectors sieres
The Vin sais it all... If it was a 305 in the VIN then thats what it left the Factory with.
Less than 200 TOTAL 350 Verts were made both Chevy and Pontiac included in the total. To my knowledge there were 4 IROC 350 Verts, 42 Formula 350 Verts and 139 GTA or TA Verts made from 1987 thru 1989. The kicker is that all of the Verts which have a 350 were ALL Conversions by ASC. Basically they are IDENTICAL in every way to what a "Factory" Convertible would have been with a 350, EXCEPT the VIN would be 1G?F?218 A "Factory Vert" would have been 1G?F?318.
The reason why Pontiac and Chevrolet did not offer a Vert with a 350 mostly speculation, ultimately it came down to Fuel economy with the 350 installed in a convertible as the car would have been assessed a $1200 Gas guzzler tax if they were sold directly thru Chevrolet or Pontiac. The Torque of the 350 is not significantly greater than a 305, even if there was an issue a little bit of extra stiffening for the 350 could have easily been achieved. Basically the torque arguemnt does not hold water in my book.
DOes that make sence?
Less than 200 TOTAL 350 Verts were made both Chevy and Pontiac included in the total. To my knowledge there were 4 IROC 350 Verts, 42 Formula 350 Verts and 139 GTA or TA Verts made from 1987 thru 1989. The kicker is that all of the Verts which have a 350 were ALL Conversions by ASC. Basically they are IDENTICAL in every way to what a "Factory" Convertible would have been with a 350, EXCEPT the VIN would be 1G?F?218 A "Factory Vert" would have been 1G?F?318.
The reason why Pontiac and Chevrolet did not offer a Vert with a 350 mostly speculation, ultimately it came down to Fuel economy with the 350 installed in a convertible as the car would have been assessed a $1200 Gas guzzler tax if they were sold directly thru Chevrolet or Pontiac. The Torque of the 350 is not significantly greater than a 305, even if there was an issue a little bit of extra stiffening for the 350 could have easily been achieved. Basically the torque arguemnt does not hold water in my book.
DOes that make sence?
Re: 89 convertable Iroc-z collectors sieres
Hey okfoz,
I have seen that you are knowledgeable on production numbers. Is there any way to extrapolate from known percentages the number of 87 IROC verts with manual trans and G92 (3.45)? I have seen the debate around the 1007 number and I have been told anywhere from the teens to 100 for this car. Any input would be greatly appreciated.
I have seen that you are knowledgeable on production numbers. Is there any way to extrapolate from known percentages the number of 87 IROC verts with manual trans and G92 (3.45)? I have seen the debate around the 1007 number and I have been told anywhere from the teens to 100 for this car. Any input would be greatly appreciated.
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Joined: Mar 2001
Posts: 14,298
Likes: 197
From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
Re: 89 convertable Iroc-z collectors sieres
Unfortunately no, I don't have that detailed information on the verts...
Since 1987 was unique for Chevrolet, I do not think it carried over into 1988. As there was only two ways to get a Convertible, with the LG4 & Automatic, or the LB9 & M5. As to what percentage of the LB9/M5 cars had the G92 might be a mystery forever, it may actually be Zero, I really do not know.
After I said that I suspect you have one?
John
Since 1987 was unique for Chevrolet, I do not think it carried over into 1988. As there was only two ways to get a Convertible, with the LG4 & Automatic, or the LB9 & M5. As to what percentage of the LB9/M5 cars had the G92 might be a mystery forever, it may actually be Zero, I really do not know.
After I said that I suspect you have one?
John
Re: 89 convertable Iroc-z collectors sieres
I do. It is a factory (VIN 3) LB9 M5 with G92. It was originally owned by a GM executive. I am the third owner with 30K original miles. I think I have found that 87 and part of 88 were the only years the manual vert could be ordered with G92. Percentages for non-vert IROCs which, if projected to the verts, suggest far fewer than 100 made. Though there is no way to tell, and as you state, there may never be. I am an enthusiast and appreciate your attention to detail. Thanks.
Supreme Member
Joined: Jul 2006
Posts: 1,672
Likes: 4
From: Killam, AB
Car: 1989 IrocZ Convertible
Engine: 305 TPI
Transmission: T5 - 5 Speed Standard
Axle/Gears: 3.08
Re: 89 convertable Iroc-z collectors sieres
Yeah, there is no way of crossreferencing option combinations. It is possible to play with some of the individual RPO option production amounts, but any conclusions are totally guessing and not documentable. Examples . . .
Facts
Total 1987 Camaro production . . . . . . . . 137,760
Total '87 IrocZ (RPO B4Z) production . . . . 38,889 - or 28.2% of total production.
Total RPO G92 (only with B4Z) . . . . . . . . 10,533 - or 27.1% of IrocZ's or only 7.6% of total '87 production.
Total of '87 production with the M5 . . . . . 22,651 - or 16.4%.
Total '87 Camaro convertible production . . . 1,007
Total '87 Z28/IrocZ convertible production . . 744
Playful guessing numbers based on production facts . . .
If only 16.4% of total '87 production were 5 spd's, then if applied to the 744 Z28/IrocZ convetibles, that would be only 122 Z28/IrocZ's convertibles had the 5 spd tranny.
Etc, etc. I'll let your imagination take over.
This is where a lot of the "I heard this many" and "only this many had this engine with that tranny" etc come from. While some might be good guesses, that's all they are is guesses. It would be nice if it was possible to document the exact numbers because those are the only numbers that can truly have a direct effect on value and rarity. But we are still able to say generally what is a more rare car than others, but often not to the exact number based on RPO combinations.
Facts
Total 1987 Camaro production . . . . . . . . 137,760
Total '87 IrocZ (RPO B4Z) production . . . . 38,889 - or 28.2% of total production.
Total RPO G92 (only with B4Z) . . . . . . . . 10,533 - or 27.1% of IrocZ's or only 7.6% of total '87 production.
Total of '87 production with the M5 . . . . . 22,651 - or 16.4%.
Total '87 Camaro convertible production . . . 1,007
Total '87 Z28/IrocZ convertible production . . 744
Playful guessing numbers based on production facts . . .
If only 16.4% of total '87 production were 5 spd's, then if applied to the 744 Z28/IrocZ convetibles, that would be only 122 Z28/IrocZ's convertibles had the 5 spd tranny.
Etc, etc. I'll let your imagination take over.
This is where a lot of the "I heard this many" and "only this many had this engine with that tranny" etc come from. While some might be good guesses, that's all they are is guesses. It would be nice if it was possible to document the exact numbers because those are the only numbers that can truly have a direct effect on value and rarity. But we are still able to say generally what is a more rare car than others, but often not to the exact number based on RPO combinations.
Last edited by Iroctopless; Jul 8, 2008 at 10:31 AM.
Member
Joined: Feb 2008
Posts: 348
Likes: 0
From: Pensacola, Florida
Car: 88 IROC Z Vert CZA3
Engine: LB9 5.0 tpi
Transmission: MM5 5 spd
Axle/Gears: G92 Performance
Re: 89 convertable Iroc-z collectors sieres
Unfortunately no, I don't have that detailed information on the verts...
Since 1987 was unique for Chevrolet, I do not think it carried over into 1988. As there was only two ways to get a Convertible, with the LG4 & Automatic, or the LB9 & M5. As to what percentage of the LB9/M5 cars had the G92 might be a mystery forever, it may actually be Zero, I really do not know.
After I said that I suspect you have one?
John
Since 1987 was unique for Chevrolet, I do not think it carried over into 1988. As there was only two ways to get a Convertible, with the LG4 & Automatic, or the LB9 & M5. As to what percentage of the LB9/M5 cars had the G92 might be a mystery forever, it may actually be Zero, I really do not know.
After I said that I suspect you have one?
John
My window sticker is posted on my home page.
http://www.cardomain.com/ride/3013097
Cool - guess my roc is in that "far fewer than 100"
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Joined: Mar 2001
Posts: 14,298
Likes: 197
From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
Re: 89 convertable Iroc-z collectors sieres
One of the biggest problems is the fact that its all sepculation... We really do NOT know how many were made... You might contact Chevrolet and ask them they may eventually have the breakdown...
John
John
Member
Joined: Feb 2008
Posts: 348
Likes: 0
From: Pensacola, Florida
Car: 88 IROC Z Vert CZA3
Engine: LB9 5.0 tpi
Transmission: MM5 5 spd
Axle/Gears: G92 Performance
Member
iTrader: (1)
Joined: Jul 2007
Posts: 174
Likes: 0
From: Kettering, Ohio
Car: 1988 Iroc convertible
Engine: 305TPI
Transmission: T-5, swapped it in.
Axle/Gears: no clue, but I'll learn
Re: 89 convertable Iroc-z collectors sieres
you're friggin killing me Gator. What a nice car. Went to cardomain on your ride for the first time, seen you lots here. Wow. Wow. More motivation to get my basic IROC as good as it can get. Wow. Then I go to Topless's domain. Wow. At least I can see what I'm shooting for.
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