Dont know about the 4 speed, but my 63 w/230 and 3 speed muncie will do 80-90 if passing, but I try and keep her under 70 due to age


http://s971.photobucket.com/albums/ae197/jon63c10
1963 c-10 shortbed stepside 427 BBC T16 HD 3 speed
1963 c-10 shortbed fleetside 348 "w" 1st gen big block & powerglide