Hello everyone! I'm new to the site and hope I can find some help. I've got a 1970 challenger with the 440 with the A727 auto. I'm looking at putting 3.91s in it but after a friend of mine ran the numbers, I'm not liking the idea of 3500 rpm at 70mph. Looking for suggestions and tips on a possible transmission swap. Right now I'm thinking either the A518 or A833 just don't know how difficult it would be to go from auto to manual? Also, I'm unsure as far as how easily there options will play with 440 and E body. Any and all help would be greatly appreciated.
Thanks,
Matt