I have a 89 Irocz 305TPI... Why does it only have a 115 speedometer. Shouldn't it have a 145 speedometer... It also has standard rear brakes, not disk... This is a number matching car....So it's not a clone.

 

Not every TPI IROC came with either of those. Actually, if i were to guess i would say at least 3/4 of all IROC's didn't come with 4 wheel disc, and 145 mph speedo's i believe were either options or standard on only the 350 IROC's and maybe the manual 305's.

 

The 145mph speedometers were only in the 350tpi equipped cars and 305s with the rpo code G92.As for the drum rear brakes I think that mostly the base Irocs/Z28s got them.

 

not sure thats right....my IROC has the 145 speedo in it and it was originally a 305 TPI automatic car....w/ DRUM brakes.
As far as the G92 goes im not sure b/c the RPO stickers are scraped off everywhere when I bought it.

 

i dont know about the speedo

But the disc breaks were an option on every car. They didnt even come standard on the 350 irocs you had to check that option off. There were a lot of things that were optional on these cars. You could get irocs with 15" wheels. There was the aluminum ds option. etc

 

Well I guess that there are misinformation out there but I was just going by what I had read over at thirdgen.org. BUT anyway I beleive that most all G92 cars had disk brakes which I was really referring to the 145mph speedo in that post about the G92 code.There was the option to delete the disc brakes option when getting a car with that particular code.

 

Thanks Guys...............

 

Doug791, "ALL" 350TPI 3rd gens had rear disks, it was a stadard option that came with the B2L (the RPO code for the f-body L98 motor) package including an oil cooler, 145mph speedo, and the borg warner 9 bolt rear in the 87-89 350TPI cars. Just thought id clear that up.

J.

 

In those years everything was a extra cost option. And GM had another thing going for it when one option required additional extra cost options.
For example: RPO B2L 350 TPI required a Atuomatic, Disc brakes, oil cooler, Limited slip axle, 245/50/16 tires with 16" wheels and so on. Now you have a idea how GM did it then. Even the IROC package had three levels of options.
And don't forget the engines, the Carb and later TBI 305's were the standard motors. So a IROC could have and did not have a lot of options. Depended on the Dealer or what the original buyer ordered.