I know the entire history of what speedo came in what third gen. However, I've heard rumours that some convertibles didn't get the same speedo as it's coupe counterpart. Here's what I know about coupes:

1986
145-mph speedo in late production Z28/IROC-Z's with 305 TPI.

1987
145-mph speedo in Z28/IROC-Z's with 305/350 TPI (true for 305 TPI convertibles too).

1988 - 1990
145-mph speedo in IROC-Z's with 305/350 TPI.

1991 - 1992
145-mph speedo in all Z28's.

Is what I state true for convertibles too? I have heard some IROC-Z convertibles received a 110-mph speedo. Can anyone verify this or dispute any of the above?

------------------
Willie

Supercharged 1987 305 IROC-Z, Daily-Driver, Emissions-Legal.
Former Paxton (6-psig): 12.57 @ 111 mph.
Former Paxton (6-psig) & former 50-hp nitrous: 12.04 @ 114 mph.
ATI D1SC (5-psig):
12.26 @ 113.55 mph
ATI D1SC (10-psig): Projecting high 11's.
Future ATI D1SC (15-psig): Gotta catch them pesky 26-psig boosted TTA's!!

http://willie.camaro-firebird.org/

1987 "20th Anniversary Commemorative Edition" Z28 Convertible -- Super Chevy Show Class Winner, 1998.

 

What I heard (and read) was that the convertibles didnt get the V (or was it already Z?) rated tires, and came with a speed limiter... and a speedo that didnt read as high as well. I think that was around 90 or 91.
Im surprised you dont know for sure. LOL!

 

I don't know EVERYTHING..... At least I admit it when I don't.

Willie

 

True. Willie would never steer anyone wrong for the sake of pride. That said, my 86 convertable w/ 305TPI auto has a 145 speedo, if that helps.

 

I'm guessing it doesn't because your car started it's life as a hard top and was converted sometime after it left the factory.



------------------
The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah

 

My 92 Z vert only has a 110 speedo, also came from the factory w/ a 105 limiter and obviously, the non-V rated tires. Of note, my car was F41, not an FE2 car. However that figures into your breakdown.

------------------
Ed Maher - Moderator @ The Carb Board
92 Z28 Convertible - Quasar blue / Tan top
LB9 4L60 GU2 G80 - stock, soon to be sleeper
-=ICON Motorsports=-

- Definitely prototypes, high powered mutants of some kind. Too weird to live, too cool to die

 

My 89 IROC-Z with 305 TPI/Auto, and 245/50/16 Z rated Goodyear Gatorbacks has a 115 mph speedo

------------------
Rick89IROC
Black 89 IROC-Z Convertible 305 TPI
13.95 @ 98.23
DGGM 95 Impala SS
13.78 @ 98.28

 

I don't know why I didn't volunteer information on my car earlier, so here it is:

1987 Z28 Convertible
305 TPI
5-speed
No G92
145-mph speedo
No speed limiter

The speedo is no different than a simiarly equipped 1987 coupe. I bought my car from the original owner and it is documented.

It appears the 1989 and newer convertible Z28/IROC-Z's got the 115-mph speedo and a speed limiter. Are there any 1988 convertible IROC-Z owners out there?

Is there an RPO code for the 145-mph speedo?

Willie

 

My '89 IROC-Z vert has the 115 mph speedo. The vert has the 305 TBI with a T5 and it came with the 15" wheels.

 

My 90 Iroc Convertible came with the 110mph speedo.

------------------
1990 Iroc convertible,305 tpi,Black with black leather interior,lowered,Taylor 8mm wires,K&N's

 

Wow, after 32K miles I can't be sure if my 92Z28convt5spd has a 110 speedo! I'm 99% sure it does. I know it sure cuts out at 110 due to the speed limiter!
Came with stock Eagle GA tires.


------------------
Rob P
89RSconvtZZ4TPI
Edelbrock Hi-Flow Intake
SLP Dual Cold Air Intake
1 5/8" Headers
Semi-Siamesed Runners
MSD6AL/AdjFPR/IROC frnt@rear swaybar/wonderbar/steeringbox/alum drvshaft/ Alston SFC/3:23posi disc rear/MAC LCA/H.Adams Panhard Rod/KYB struts/ shocks/
92Z28convt5spd
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!

 

Willie,

Back in 89 when my car was still all stock, I could top out the 115 speedo. So it looks like I had no speed limiter, unless it was set above 115 mph

 

It does have a 145, and I believe it started out as a t-top car, but it's an 86 and the ASCMcLaren sticker in the door says it was converted in 86..

 

The 145s started coming in some later 86s, but because your car wasn't a convertable when it left the plant, it doesn't necessarily prove anything except that hard tops were available with the 145.

------------------
The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah

 

You want proof? I've got it. I bought a brand new 1986 Z28 with a 305 TPI from the local Chevy dealership in August of 1986 (the '87's were just starting to arrive). It had a 145-mph speedo.

Willie

 

Willie, I've got a 91 Z28 convertible. It has the 110 speedo, It came with Z-rated tires and has no speed limiter. It is an FE2 car, but not a G92. if ya need anything else my S/N is JakeF91Z

[This message has been edited by jakef2003 (edited June 20, 2001).]

 

1992 TA Vert
120mph speedo
Came with Z-rated gatorback tires
305tpi

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http://sites.netscape.net/bulldogfrazier/homepage
+
http://www.fracoinc.com/


Keep your ride shinning with pride

 

I was just offering some information for comparison "for what it was worth", not trying to "prove" anything; why are ya pickin on me? hehe.

And it was a T-top car... At the top/center of the windshield, there's a "cross-section" of a brace that looks exactly like the one on a t-top that I cut the center-strip off of. And it has the provisions for t-tops in the trunk.

And I'm under the impression that no convertables "left the plant" as a convertable but was sent from the plant to ASC to be converted.

 

You're right, but there were still differences. The cars that were sent to ASC directly from GM were t-top cars, but were not fully assembled. Their VIN and RPO codes also reflected their convertable lineage, wheras something done after it was purchased would not have any affiliation with GM, so the VIN and RPO codes would read only as a t-top car. In the long run, I doubt it makes any difference except on resale value, but from a standpoint of a buyer, I'd only buy an original "factory" (I use that term loosely!) convertable, unless I found an ASC conversion and had no interests in keeping it original. I guess I'm just funny like that.

------------------
The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah

 

I'm a 88 IROC convert. owner. I am not the original owner, but seemed to be all orignal when I purchased. The car is equipped with the 145 mph speedo. Does have the G92 option, 305 TPI, & auto.

Never new they put limiters on camaros (what the hell for???).

Hope this helps your statistics.

------------------
When the green flag drops, the bull%#$@ stops.

1979 Z28 w/427 Street/Strip car
1988 Iroc Convertible

 

What would the VIN read? I'm assuming it's a third or fifth digit difference?

 

WRONG!!! Not all 91-92 z28's got the higher speedo. My t-top 91 has a 110 speedo and it is original. It has the 305 auto 4. I think more like the g92 cars or the 350-auto or the 305 5-speed cars got the 145 speedo.

 

I have a '91 Firebird. My Father Bought it straight from the dealership.

It has a 145 mph Speedo and a limiter at 109 mph.

Didn't find out about the limiter till '98 when i was driving through Nebraska.