RPM's

The tire size table shows them to be a 26" diameter tire which is a little bigger than my 245/60/14 . I would suggest playing around with the tremec calculator that uses gear ratio and tire size to compare RPM , your mileage still should be better than 80 miles a tank thats like 4.8 miles to the gallon , how black are your plugs ? Are your neighbours sucking on your tank at night ?