Yes. FOR THE RIGHT CIRCUMSTANCE, ANY THING IS WORTH IT.
The ideal gearing for economy was cracked back in the 1950's but we had to wait till the late 1970's and early 1980's for the formula to be re-arranged for best miles per gallon for a given average cruise speed. It is based on the from the
Index of Thermal Efficiency, found in French Grand Prix and English RAC litrature by Hodges,
and was revised in 1980 for the
Australian Total Economy Run, to use the average frontal area and overall cdA drag factor for a late seventies, early 80's car. See
http://www.snooksmotorsport.com.au/i...d=31&Itemid=39
All esle being equal, there is no difference in fuel economy between a 165 hp 300 I6 and 165 hp 351W if they are optimized induction and have the same kind of gearbox optimised. Same with a 500 hp turbo verses a 500 hp non turbo.
The Snook formula copies the age old French Index of Thermal Efficiency for optimizing 62 mph fuel economy.
The Dimensional analysis shows the inputs are here
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http://vb.foureyedpride.com/showthread.php?153148-4-2-V8-Info-and-pictures-needed/page2"
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https://fordsix.com/threads/gear-suggestions.76051/"
Coefficient Of Drag in Cd
Frontal Area Sq. Feet
Vehicle MPH = 62
Vehicle Weight (varies road load at 62 mph)
Tire Pressure (varies road load)
Brake Specific Fuel Consumption in US gal/hp-hr.
Drivetrain Horsepower loss AT 62 MPH