Can I tell what rear end I have with this 73 RR fender tag?

[moparmarks]

A 73 Road Runner should have an 8 1/4 rearend

This chart though good for identification is inaccurate when pertaining to years and models.
73 RR w/ 318 would have an 8.25. With 400 should have a 8.75. Late built car could have the 9.25.

 

[monaco66coupe]

Funny how stuff fits, I sold a70' Challenger R/T a couple years ago that had a 9 1/4 rear end in it. Who knows how it got
there.

 

[daredevil]

try this http://www.wallaceracing.com/calc-gear-tire-rpm-mph.php

 

[b_body_hopeful]

That helps, thanks.

 

[dart1962_440]

This chart though good for identification is inaccurate when pertaining to years and models.
73 RR w/ 318 would have an 8.25. With 400 should have a 8.75. Late built car could have the 9.25.

I agree. My 73 Coronet Wagon has a 400 4bbl HP is a June 73 build and has a 9.25 axle