red30011

Theres prolly a thread on this but didn't find it in search so here I am...
Just was wondering if mine really is a iroc or just something the previous owner stuck badges on? Main reason i'm doubting is because it had a 305 in it before I replaced the motor and the vin number shows the car as a 305 car.
Just wondering if that means its another model or if theres anything else I can look for to id the car?
Thanks
Zach

AmorgetRS

iTrader: (6)

The IROCs came with 305s and 350s. If it is a 88+ and had the 305 TPI motor, it's an IROC, because there wasn't another way to get a TPI motor. If it's pre-88 then it could be a Z28 or an IROC. If you have the SPID sheet (lists RPOs, it's supposed to be in the center console) look for the RPO B4Z.

Here is some good reading:

http://www.iroczone.com/2009/10/iroc-z-spotters-guide/

red30011

Good read,thanks. Still need to look at my rpo code(now that I know roughly where its at) to be completely sure but all my worrys seem fine. By reading that it sounds like mine was a true iroc. The 85 mph speedo and the 305 scared me but seems norm for mine.

JamesC

iTrader: (5)

That's what my 85 IROC was equipped with. Hard to believe.

JamesC

grumpygreaseape

does it have the "wonderbar" across the frame up front? it goes across from frame rail to frame rail next to the steering box. if it looks like it has been bolted up for a while-you probably have an iroc.

InfernalVortex

iTrader: (4)

Thats a good point grumpy. I doubt people making a fake clone would bother with the wonderbar. It's not hard to add, it's just obscure. Easy to ignore.

In case you dont know what it is, here is mine. It's a factory one from a Z28, it' the black bar above my sway bar.

John in RI

iTrader: (167)

I recently bought an 86 that was labled as an IROC but I had to wonder since the RPO tag was missing, the speedo was 85 MPH, the Tach had a 4500 Yellow line, and the car has a facory Carb engine. I used several of the suggestions made by others to verify that it was really an IROC.

Something not mentioned; You could also check the yellow tags on the front springs for the 'BZW' code and the Rear Springs for the 'NNL' code. The Wonder bar is a good clue - but it's really quick and easy to install. There are very few people that would install a set of IROC front springs to try and pass off a Z28 as an IROC ! MAYBE the rear springs - but the fronts are to much work for most people !!

Drew

iTrader: (58)

Spring codes aren't a reliable way to verify anything but the springs. It's not unusual to find CDB, BZW, and BZX front springs on Z28s without the Iroc package, or even base models with V8s.

John in RI

iTrader: (167)

You should not find ANY front Spring code other than BZW on an IROC. 'Logic 101'..... Worry less about if the code IS there ( proves nothing ) and worry more about if the code is NOT there. ( possibly disproves ) I ONLY say "possibly disproves" because they could have been removed/replaced from the IROC after leaving the factory by any 15 Y/O kid with basic hand tools.

It's not a 'dead giveaway',..... but it is 1 more way to ID the car as an IROC and not a Coupe when there is no RPO code sheet present. Since there is no VIN designation for an IROC anyone can turn ANY Camaro into one. I'm quite sure that I could turn my latest 86 IROC into an 86 Coupe and no one would ever know - but then I'd have some one trying to sell me on the idea that a Coupe had factory BZW front springs ! Since there is not FIRM way to prove and IROC is an IROC, all we can do is look for IROC specific items to help DISPROVE that it is authentic. Since the front springs are one of the hardest parts to remove and install they are one of the most reliable determining factors.

I have owned over a dozen Z28's and have NEVER found a BZW code on any of their front springs; Yet Every IROC I've owned has had them. The special suspension It is one of the things that turned a 85-90 Z28 into an IROC ( or IROC-Z). I'd believe that a Sports Coupe got BZW front springs from the factory as soon as I believe that a Coupe got a TPI power-plant from the factory - but that just MY opinion.

Drew

iTrader: (58)

You're welcome to your opinion. Even if it is incorrect. I've seen no discernible difference between the suspension on a Z28 with B4Z and a Z28 without B4Z. Better yet I pulled a 34mm front sway bar off my 84 V6 Sport Coupe that came with F41. There's really nothing special about the suspension under an IrocZ. Also I've got at least 6 Irocs in the information I surveyed years ago that came with BZX front springs, and a couple others that came with CDB springs... I stopped looking at that point because your theory doesn't hold water. Believe what you want, but BZW springs is no indicator whatsoever that the car is/was an IrocZ.

Drew

iTrader: (58)

I just went and checked, and one of those rare BZX Irocs is parked in my garage. I guess it isn't an Iroc by your logic. It's one of these rare CC1/L98 cars too... Sorry about the blurry pic, but it's an old camera and the car is under a cover.

grumpygreaseape

as far as the coil springs found under an iroc, they were specific to the iroc package. my original factory brochure states in the iroc-z features "trim height and center of gravity lowered from z28" also my car and driver wrote that gm would hand pick the springs for the iroc to drop it a half an inch or so compared to the stock z28. irocs had a lowered ride height compared to a standard z. i dont know about the hand picked part but irocs did have specific springs. mine are bzw and nnl i can still read the part number for the rear springs-10018091

Drew

iTrader: (58)

You're going to argue with a SPID?

grumpygreaseape

im not arguing with anyone. peace out.

Drew

iTrader: (58)

That's funny, because I posted a picture of a SPID showing B4Z and the spring codes 6ZX and 7ZX. That's indisputable proof that at least one IrocZ had BZX springs. You can believe the marketing if you want, or you can believe the part numbers on various cars, and the SPID which GM and the dealerships used to order the correct service parts. GM used three or four different codes for front springs on cars with level III suspensions. BZX, BZW, and CDB are the most common codes. You will find these springs used interchangeably on all kinds of level III cars. Sometimes you'll even find a car that has a CDB on one side, and a BZX on the other.

There is nothing special about Iroc springs, they're the same as WS6, or level III in any other Camaro or Firebird.

grumpygreaseape

i dont know you and i draw the line when you start calling me crazy. your cyberspace life protects you. whatever subject it is, it isnt worth discussing with you.

Drew

iTrader: (58)

Here's a couple more B4Z/BZX Irocs from older threads just for fun.

John in RI

iTrader: (167)

Remember - my logic is based on not having an RPO code sheet to work with.

A wise man once said,

Post a pic of your spring tag and I'll believe it. Ya',... I'm scheptical. What I know is what experience tells me and I will continue those beliefs until I am proven wrong. Your RPO sheet doesn't do that.

6ZX - Spring, computer selected, front, left hand
7ZX - Spring, computer selected, front, right hand


Let me admit; that's the first IROC RPO code sheet that I've ever seen with 350 and T-Topcs......

Drew

iTrader: (58)

The SPID specifies the codes with numbers to indicate the position of the parts on the car. Sometimes the left/right springs are different codes. 6?? is always a front left spring, 7?? is a front right, 8?? is the rear left, and 9?? is the rear right. This is always consistent. Obviously the springs use the same broadcast code regardless if they're to end up on the right or left side of a car. With the exception of CDB and potentially other codes I haven't verified, front springs always use the B?? codes, and the rears are nearly always N??.

I'd be more then happy to get a snapshot of the actual paper tags on the springs in the car, but the front end is burried in a one car garage, it's dark, and I don't really feel the need to further prove my point.

Drew

iTrader: (58)

Here's an 89 Iroc, L98/CC1, with BZW springs just to show that more then one code was used... Imagine that, another L98/CC1 car. How do rumors like this get started anyway?

JamesC

iTrader: (5)

My 85 IROC RPO's show 6ZW (Computer Selected Front Left hand Spring) and 7ZW (Right hand). The rears are 8NL (left hand) and 9NL (Right hand).

With varying springs (though I don't exactly know what that variation means), I wonder how Moog, for example, can manufacture IROC replacement springs?

JamesC