blubuckaroo
Grease Monkey
I too asked about fuel mileage on another eb site and immediately got flamed. A lot of responses about "cool factor" and "who cares about gas mileage ".
The reason I asked about mileage was my bronco at that time was a 73 c4 with shift kit, 351 Windsor, 31x10.50 bfg. 4:11 gears.
Best I could get was 10 mpg.
My prior broncos would get around 15 mpg.
My 70 pure stock 302 with small tires,4:11 gears leaded regular gas and lived at 5000 ft elevation would get 15 mpg.
My 71 stock 302 small tires 3:50 gears, also. Ieaded regular gas low elevation, also around 15 mpg.
I think that the smaller tires make a big difference in mileage. Those large tires are like 4 big flywheels to turn along with the rolling resistance.
Even with corrected gearing, bigger tires have several things that negatively affect mileage.
The greater centrifugal weight take more power to get rolling.
The rolling resistance of bigger tires takes more power'
Wider tires are less aerodynamic than narrow tires.
Also, many don't realize that a well tuned engine will be an efficient engine. You can't just take a carb or distributor out of the box and expect it to run right.
Last year we attended the Northwest Bronco Roundup, and you could tell the well tuned Broncos by the smell. I'm sure the stinky ones are missing out on efficiency and performance as well.