My 1985 E150 Van has the 300-6, with the the 4 speed manual overdrive transmission. It's totally stock, everything. It's works pretty good except the rear end gear ratio is too conservative. It's got a 3.00 ratio ( ford 9 inch rear end) and I use a 235 X 15 tire. I don't even need (or use) the O.D. What gear ratio do you experts out there suggest for general purpose driving? I was thinking 3.5, 3.7, or 3.9.
I live in a very hilly city, ocasionally tow a 1500 lb boat, and I'm on the freeway everyday.