My '59 3800 with a 235, a stock 4-speed and a 4.56 gear got around 12 MPG, so unless you've done something out of the ordinary, your mileage is pretty far away from normal. I had 18" tires on the original split rims.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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