hi ive got a 85 f150 302 4x4 w/ t18 trans 3.75 rear diff and its turning a lot of rpms going 65 ( base model no tach yet ) i have 28" tires on it now what kind of rpms am i turning now? and how much of a drop in rpms can i expect with a 31 " tires thanks!

hey from pa ! im livin in nw pa between erie and pgh as soon as i figger out how to post pics of my 85 f150 4x4 i will!