I believe in the real world you will find that by gearing the vehicle that low the engine will be lugging so much you will not be at the most economical mpg. Fuel mileage is not all RPM. It's also load, throttle position, and the amount of power you're asking the engine to produce. You could have the truck geared low enough to be at 1000 rpm at 90mph and find that you have to have the pedal on the floor just to maintain speed. With the butterflies at max open fuel consumption will be max (depending on air flow) and mpg will be down. There are so many variable to balance, no wonder getting max mpg is no simple task.

I've actually hears that some mustang owners have when to higher numercial gears and seen an increase in MPG because the engine wasn't lugging.

 

Aftrmidnite do you mean the Ford Escape HEV 40MPG hybrid.


http://www.ford.com/en/vehicles/spec...al/default.htm

 

It wasn't the Escape, someone at work told me about a 40 mpg Ford crew cab couldn't find anything about it. Was on a military base for work, and I was telling him it was a hoax. The RONK told me about the trucks web site, it was a super duty, with built in 50 cal. machine guns, laser system, ran flat tires with repressurization system. GPS with autopilot. An incredeble towing capacity. Production Gasoline engines only turn 20 to 30% of their gasoline energy into drive shaft energy. The rest is lost in heat, wasted mechanical energy, and chemical energy; IE exhaust pollution.

 

No offense to anyone here,
But 1/2 of the stories I read on this thread seem very unbelievable.
As for the 460 or motor of that sorts getting 40 mpg, I really doubt that, even with lower first gear, over drive etc.
When I swapped my 2.75 gears to 3.70 in my 390/C6, I didnt get that much different gas mileage, and thats almost a full number drop on the gear.
Sure, I bet you can get between 5 and 10 more miles per gallon out of almost any vehicle, but getting up around 50+ is a bit crazy
Also, you must figure in power/weight ratio
Thats why motorcylces can easily get over 50mpg... They weigh nothing, and they make plenty of power.
Just my 2 cents

 

I'm still looking for the MPG rating, but here is the truck. http://www.nationaldefensemagazine.o...cle.cfm?id=709

 

40 mpg half ton hum, sign me up,
we may see the day it happens but not likely,
I heard the same story about a guy with a chubby, 20 miles to the gallon one way and 20 miles of pushing to get it back home.

 

i'm going to raise the BS flag. sorry
on side note: i can get the fuel economy computer thing to read 99mpg on the mercedes. just coasting downhill though with cruise control set at 73mph. but hey, if i go downhill for 20 miles(from park city to salt lake city) and average 99mpg...i've use a 5th of a gallon. not bad, huh.

 

And did you hear the one about the guy who invented a cheap and renewable gasoline alternative? The oil companies bought him out and made him sign a gag order. hmmmmm? lol I love urban legends.

 

Here's a thought. According to snopes.com, that story originated in the 1920s or 1930s. Now gas was what, a NICKLE a gallon then? But people were still concerned about how much it was costing them. 'Course that was back when pennies were money!

 

76supercag2 is right on in his post. The biggest reason for fuel savings on an overdrive trans. is that you have less friction in and on the motor, not because if the motor uses x amount of fuel at 2500 it will use 20% less at 2000 RPM given the same vehicle speed. Given the same driving style a vehicle w/ lower rear end gear (numerically higher) will often get BETTER economy around town than a higher geared vehicle. but it all depends on the weight, aerodynamics, engine (especially the cam), fuel tuning, timing, trans type and setup,overall drive ratio(including tires) what speed you want the best economy, not just engine RPM. It's impossible to have ideal economy and performance everywhere. anyway, I agree, HOAX. I'll have to use that one JONDIRT, funny.

 

My opinion on it is, if there was a conspiracy, then you wouldn't be seeing hybrid cars on the road because they can get the claimed high gas mileage but they are actually for sale. If the technology was there, at a reasonable cost, I believe that one of the automakers would have unleashed it by now, especially since the current trend is large trucks and SUV's that make the comapanies good money. If they were able to get far better mileage you would be seeing it available because then people would be able to buy them without having to worry about poor mileage. Even if it an expensive technology, I think you would be seeing it available on top end cars. I also believe that in the long term the price of gas would sky rocket due to the oil companies not selling as much oil and still wanting to make a profit. There are so many versions of this story, and even if it did happen once, I don't think the auto makers would them slip out as often as you hear the stories about them. This is all my opinion though, I'm by no means an expert.

 

I was talking to a retired guy at a motel once. He drove around to the the car shop circuit in the summer selling automotive art that him and his wife made. He had a big mid 80's station wagon that he claimed he got 50mpg out of. Here was his story: In the mid 80's, for a couple years, GM put hard drives in the Vette to control the cpu. He took the engine and harness out of one of these Vettes and put it in his SW. During his travels at the car shows he met a GM rep whose job was to travel around and reprogram fleet vehicles. This guy just happened to have one of the programmers for the old Vettes. They were both doing the circuit anyway so they played with the thing. They tried maxing out the MPG on the trip from Redding, CA to Seattle, WA and he got close to 55 mpg average on the trip. His station wagon would barely make it over the hills and lugged from a stop. He said it wasn't worth having set that way daily, but it was great getting that mileage. His buddy wouldn't sell the programmer.

 

it would be very interesting to try that with today's engines. I wonder if it could worl to that extent. Heck, even a 25% increase (for me that would equate to about 3.5 MPG extra) would be worth a few bucks, as long as it didn't drain too much of the power!

 

is it human nature to always look for a conspiracy?

 

SHHHH...
We're not allowed to talk about that... THEY might be listening