What gear ratio for a street car w/occasional track use?

yellow rose said

I thought after 1970 all 4 speeds were the 2.47 low gear? My 72 Demon was a 2.47 low, interlocking lever side cover box.

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I cannot argue about that cuz I have no first hand factory knowledge. I had a 2.47 box and got rid of it because the low gear was not happy on the start line until about 4.10s or better with a SBM. My understanding has always been that the close ratio box was a Trans Am box, and came in with the 70up Barracuda/Challengers.