Question about non OD 833 and rpm range
now it's at 3000 rpm. Diff gears are 3.45, tires are 26.6 inch]
Did you ever check your
tach accuracy? I have found some unpleasantly large errors especially at "low" rpm (3000 or less) in more than one tach, new or used.
I also have 26.6" tires which turn 758 revs/mile (295/50R15) and 3.91 gears, so my calculated RPM at 60 mph with no o/d is 2964. Speedometer calibrated against a GPS app and it is right on at 60. So if you really have 3.45 gears I don't know why you are at 3000 with the same diameter tires! Something doesn't add up.
However, my Autometer 5" tach reads about 2800, over 150 rpm low, at that speed. It only has a gain adjustment with no linearity tweaks. I set it on the bench (with a pulse generator and an accurate frequency counter) to be closest from 4000-7000 rpm which is where it's most important. Anyhow, check your speedo and your tach. You might be surprised ;)
To your original question, yes, it's "normal" and noisy. Not good for mileage (I'm lucky to break 10 mpg at 65 mph with my overcammed 451). But I can buy a lot of pump premium for the $5k cost of putting in a five-speed OD trans...
