How do I design car for MPGs in thrme teens and have some towing.)

[Unavailableartist]

I dont expect modern numbers from 30s vehicles much less 1900 or 1910. As you probably even the model didn't have 40mpgs (25 in reality anf it wasnt made till a few after the car I intend to make) You however told me something helpful cruising speed. 2night Ill try with a top speed at or around 100 kph and see if I can reach closer to my mpg goal. The thing is not a predictable decline in mpgs some I get a gas rating as predicted i.e. 10 mpgs on the prototype panel = 10 mpgs with finished model... or a predictable 1/5 of what it is 50mpgs = 10 mpgs.

I however have managed 50 mpgs from a 2cylinder that (from the low torque and part weight) turns out to be 10 mpgs (gets me 2 or 1 1/2 stars on fuel) not bad for a a 125 engine.

But sometimes changes in gears has unforseeable effects. I.e. I try for 16 mpgs overall (give myself leeway of about 1-2 mpgs) and the amount turns out being 7 or 8. Ill try tweeking the top speed and seeing what happens.