Thought all 350s had the G92 on them...seems some of them did not have them or the KC4 code...I made a post earlier...but I have seen online L98 Codes online showing NO G92 or KC4 codes BUT did have the G80 and J65 code...correct?

 

What year? As I mentioned in my response to your post yesterday, ALL 1987 350 cars had G92. From 1988 on, it was an option.

One thing to note is the 1987 L98 had G92, but didn't carry the code. It was the only axle available with the 350, so to support the 350 requirements and the axle requirements, all of the other mandatory options were included.

 

Interesting. I did not know that. I gotta wonder why GM would even bother offering the taller axle ratio on the 88+ cars. Fuel economy was rated the same either way. Simply cheaper to get from suppliers? Who knows.

Off topic, but same idea. The early C4 TPI Corvettes with the automatic had 2.73 or optional 3.07 axle. In 1989, you got a 2.59 or 3.07 on an automatic coupe. While convertible automatics came with 2.59 or 2.73.......I would hardly consider a 2.73 to be a performance axle ratio. Certainly not on the 700R4.

 

The catch is that if an option only had one set of standard equipment features, the usual code associated with those features may not appear on the SPID.

In 1987, the 350 was only offered with one gear ratio, so there is no need to put the G92 code on the SPID since there were no optional ratios.

G92 indicates the car is equipped with an optional "performance GEAR ratio". So if a car could be ordered with a standard gear ratio, or an upgraded ratio, the G92 would appear with the upgraded ratio. In the case of the 350, there was only one ratio offered in 1987, so they don't use the G92 code.

Where things get confused is a "G92" equipped 305, generally received the rest of the performance options like the 350 would have. The G92 code still just indicates a performance gear ratio, but due to how the options were packaged, there's a strong general misconception that G92 represents a package of options.

The other nicely confusing factor, is that different things happened different years. Like 1987 L98 cars only being offered with 3.27 gears, or 91-92 L98 cars only being offered with 3.23 gears, while 88-90 could have 2.77 gears. The easiest way to know what is what from year to year, is to either study the technical database, or get a copy of the Camaro White Book and study it. Beyond that, if you only care about one year, the sales brochures and order forms, etc from that year for that car can often sort out what was or wasn't available. Just keep in mind there are always small variations that some source or other misses, and old wive's tales die extra hard.

 

Hey Drew, whats up dude. Anyways...soooooo your saying the 350s (lets stay on IROCs) did not carry the same gear thru 1990???) News to me...so...ur saying the G92 was NOT on the RPO stickers in 87 because they were all the same...but in later years it was??? Also...Drew...not trying to sound like a smart butt...however...you said that when the 305s got equipped with the G92 they seemed like a package option...well I know what the technical answer is...but is it more in reality that it was just pushed and encouraged by dealerships to actually be a package option...if that makes sense...as in 90% of some people got this and it was a package option and 10% of the others got just the performance axle...if that makes sense.

ALSO SCOTT...I recently stumbled apon these 100 something page Books I found on GM heritage foundation (where you guys I think get your answers)....Scott...with all due respect...there is and or needs to be a sticky on this!!! I assume these are the "white books" Drew is referring too?

https://www.gmheritagecenter.com/doc...let-Camaro.pdf

Am I in the right place...GM heritage foundation and vehicle kits?

 

..

 

Those pages are the "Restoration Packages" that GM provides if you are looking for information on a specific year. Those are not the White Book. There is a small booklet that breaks out the yearly differences and options. Pages from the white book are copied into the Restoration Packages that you linked to. My recommendation is to download all years you're interested in so you have them on your computer, rather than on a website that can pull them at any time.

What Drew is saying about the G92 option 'package' is that the G92 individual option requires additional mandatory options. This makes it seem like a package, but they are individual options required when ordering G92. Similar to ordering the 350 in 1987. When ordering that $1045 option, you couldn't stop there. You were required to buy the J65, KC4, G80, etc. That's where many of us believe the B2L option code came from. I believe that B2L is the 350 package that includes the L98 engine. Dealerships could not modify the required options when ordering G92.

Reid, GM offered the taller axle ratio because 1988 eliminated the lower optioned Z28. In 1985-1987, the IROC-Z was a option built on top of the Z28. In 1988, all Z28s came standard with the IROC-Z appearance package, so GM allowed the IROC-Z to be as bare bones as a previous years Z28. That's why you could also get 15" Z28 wheels on an IROC-Z in 1988. So the 1988 buyers can have a bare bones IROC-Z or they could opt for the 350 with highway gears, or they could go all out and get the top of the line performance IROC-Z with the 350 and the performance axle.

 

Drew...so you could order the G80 by itself on the LB9? Like in this photo and NOT get rear disk...?

 

Camaro White Book 1967-2011 Paperback – January 1, 2010
by Mike Antonick


GM's heritage kits usually include a hastily photocopied page or a few pages from the White Book, but if you want to know, you really need to buy a real copy. Its a pocket sized reference book to all things Camaro options. By far THE single best resource available. The gold standard.

Very busy at the moment, I'll try to check back later to address other questions.

 

It's worth mentioning, there are several editions of the White Book. I linked the latest version to the best of my knowledge. The copy in my library only goes to 1997, and is absolutely worth the $5 for a used copy. Don't necessarily need the latest version, unless you want to spend the money. Seem to remember the author or publisher has a website that offers the book for sale directly. Might be worth shopping around for the best price, since Amazon isnt really about just books anymore.


The Genuine Camaro White Book 1967-1997 Paperback – November 1, 1996
by Michael Bruce (Author),‎ Michael Antonick (Editor)

 

The SPID above is for a 1989 car. In 1989, all Z28s (IROC-Zs) with an LB9 auto or manual required only the G80 option. G80 is limited slip rear axle and doesn't require or need any other options for it to function.

 

Not too much. Taking a short break from cars since I finished rewiring the dash for the Firebird. Distracted by other hobbies and the dreaded holiday sales. Probably get back to cars after the first of the year.

In 1987 the L98 was only offered one way, they all had 3.27 gears standard. In 88 and 89, the L98 could be ordered with the standard 2.77 gears or the G92 3.27 ratio. Also in 1989 mid-year dual cats started being used, so there are two HP outputs. 90-92 all 350 cars came with 3.23 gears standard, with no optional ratio, more on these cars further down.

So any time you only have one gear ratio offered, there's no need for the G92 code to differentiate since it's the only option. For 88 and 89 350 cars, no G92 on the spid would mean 2.77 gears, G92 would mean 3.27s.

I'm not sure about 90 and 92, but at least in 91, L98 cars have the G92 code even though they all came with 3.23 gears.

As a general rule, L98 cars always came standard with J65 discs, KC4 oil cooler, and G80 limited slip. There are exceptions to the rule when it comes to J65 since at times there were shortages of rear disc brake hardware.

On the other hand, the LB9 was almost always offered in more than one variation. Usually to get a stronger LB9, it needed the 5spd, or G92, or both the 5spd and G92. G92 cars generally required the oil cooler, etc. Now you can look at it as G92 included those options, or that the stronger 305 came with those options. In my opinion, G92 is just the upgraded rear gear ratio, but it's a red flag that differentiates the stronger 305. If that makes sense... It doesn't make sense to me that G92 includes those options, since you'll have those options without the G92 code.

You can chalk up another chunk of confusion due to the 1LE option, and how it was ordered, and packaged. 1LE cars REQUIRE G92. So when you get to 1991, when the Firebird used RPO R6P for the "performance package", you won't see G92 unless the car is also a 1LE. Since that is the only time a 91 Firebird needs the code for any reason, otherwise it'd be redundant.

See my previous post about the White Book. GM's papers are OK, but best to go right to the source.

OK, so as a quick recap... When GM determined how a car could be equipped, they lumped options into packages that could be chosen, AND they required certain options or packages with some specific options. Like 350 cars only being offered with the auto, and requiring the oil cooler, etc.

Since the SPID is primarily for ordering the right service part, it generally only shows the codes necessary to differentiate between different parts. You wouldn't need the G92 code on an 87 350 car since they could just as easily go by the L98 or B2L code. Just keep in mind there are exceptions, in some cases there are redundant codes. But in general...