Option Codes

[Wayne M.]

Re: '71 Rear Axle Codes (TSB)

Just to add a little spice, remember that at the end of the '71 production run, it was brought to GM's attention that a FEW (but they don't know how many) '71 Corvettes were produced with the incorrect axle ratio, due to a computer programming malfunction. Tech Service Bulletin issued Aug 20 '71.

Some base equipment cars (which should have had the 3.08 ratio) were produced with the 3.36 (code AX or LR).

Corvettes with high performance axle ZQ9 should have a 3.36 ratio. However, some were produced with the standard 3.08 axle (code AW).

Instructed to change only if customer complains about gas mileage or acceleration.

[Terry M.]

Re: option chart in ver. 3 TIM&JG *TL*

The charts in the rear of the latest 19709-1972 manual are substantially the same as the earlier one. I don't have the paperwork in front of me, but my recollection is I made few changes to this list. I did, however, add a code for 3:08 (AW) to the 1972 list in the Chassis section

We have made no effort to establish the standard or optional ratios available with any engine transmission combination. The original Judging Manuals confined themselves to "judgeable items" and thus didn't even mention transmission codes or differential codes, and since NCRS still doesn't judge window stickers (they were ordinarily removed during new car preparation), not to mention build sheets, we have not yet explored the issues you raised.

Increasingly our manuals are becoming Technical Information Guides as the new titles indicate. As the current team leaders update them they will contain more and more of the "nonjudged" information we are all so interested in.

Terry

[Roberto L.]

Re: '71 Option Codes

To add to other's comments the NCRS pocket guide reads 3:08, 3:36 and 3:55 for econ, std and hi perf. with LS5 and M21 trans. 3:70 is also metioned as available (as Chuck said).

Roberto, NCRS #30019, RMC