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Trying to decode my rear end ratio for 1971 4spd 350 270hp coupe. From previous forums I have gather 3.36 is standard with the stamped AX code. I have attached a picture below of what I uncovered on my rear end, seems like a possible 0A11 ??? Doesn't make sense, wrong location?? Just spend little bit of time trying to degrease the #'s, maybe I just need to keep working on it. Thank you in advance!
Last edited by FirebirdStrip; Nov 3, 2017 at 09:08 PM.
The number you are looking at is the casting date. A11 would be Jan 1 1971 which would be unusual since it was a holiday. Looks like there maybe another 1 there? so A11 1 = Jan 11 1971 which makes more sense. That was the born date, a month or two later it was assembled and stamped on the bottom lip with the ratio and plant with the julien date. The older stampings had the actual dates. 336 was the ratio used with the m20 WR 4 speed. However unless you know the history it may have been changed over time.
Decoding rear end ratio
