Alternatives/Solutions

[Doza]

In light of the Holy Shit and Gas Prices threads, why not talk about alternatives, and why they're viable and why they're not. I'll get the ball rolling.

Here's my plan, and I've probably posted this back in the day, but what the hell.
Overdrive gears. And lots of them. Let's examine a Lamborghini Murcielago. 9 miles urban, 13 miles highway. Now, other than a 6.2 Liter V12 and 3600 some lb curb weight, what do you think makes this number so low, especially the highway figures? How the EPA tests these. The EPA test for highway is this: Run the vehicle at 70 miles an hour. Now, think for a second, you just dropped $279,900 on a Lamborghini, wouldn't you expect it to be capable of at least 150 miles an hour?(someone give me a top speed) So, why not operate the vehicle somewheres around 120 or so. On every vehicle, there is a sweet spot, where you get your greatest mileage, it's an upside down parabola, and the sweet spot is the highest point on it. Now, if speed limits on the highway could be considerably more liberal(like Montana's lack of one <3), then these exotics could realize their full gas saving potential, not like the execs and stars that drive them care. But next, on to the common man, whom I'm concerned about because I am him, or the common college student. If the American automakers would gear cars for higher speeds(most production vehicles today are capable of at least 100mph), or at least put overdrives in that allow vehicles to loaf at highway speeds. Now, here's another statistic for you: The '04 Z06 Corvette gets 28 highway miles per gallon! Yes, the engine is smaller and the Corvette lighter than our Lamborghini in question, but the real magic is the gearing. When going 70 miles an hour, the Corvette's engine is running somewhere in the 1200-1500rpm range, also known as loafing. This is where it gets it's 28 miles a gallon from. So why not apply this to other vehicles? Make an Inisight that has that sort of gearing, and get hella gas milage from it. That's my two cents.

[lightweight]

The tests are done in a standardized way. All vehicles are driven the same way and they get a mileage figure. As you said before Doza the cars have a constant speed.

In real life cars don't have the same speed for more than 1 sec. Throttle inputs are constant. Actually, pressing the throttle partially is the reason for wasting so much fuel. Only if the gas pedal is pressed 100% does the engine fulfill its promise of about 30% of efficiency. In real life, where Joe thinks that partial throttle means less gas, the efficiency drops to about 15-17%.

Also cars like the Corvette have overdrive ratios. This way they travel at 1000 - 1500 rpm during the official tests. But during every day driving they won't be treated this way. Be sure that the owner of the F430 will rev it up like hell and burn tyres and gas.

Your idea is a good one provided that its used by the every day driver. I doubt that, since it needs a lot of education to succeed.

[Matra et Alpine]

This was provided in the 60s on 'sportscars' so that the aggressive gearing for performance didn't' mean screaming along at 5000 revs doing 70mph

It was done by an extra gear on the output of the gearbox. Overdrive. For one revolution of the input shaft there was more than one rev of the output. The advantage of overdrive was that when you wanted acceleration then you just flicked the overdrive off and once past flicked it back on again - no need to use the clutch.

Clutch is the hassle in providing more gears and a very tall top gear UNLESS you either put a bit stroker V8 in ( NOT fuel efficient ) or run a diesel.

As auto gearboxes are inefficient it's all moot anyway

With modern gearboxes and auto double clutches it's feasible to do this VERY efficiently. BUT the cost coudl be prohibitive in all cars except those owned by folks who dont care about gas prices

[Doza]

Your idea is a good one provided that its used by the every day driver. I doubt that, since it needs a lot of education to succeed.

It's darwinisism. Those who don't deserve to be on the road would probably die a death. A death of doom.

[h00t_h00t]

Diesel motorbikes are the future, 100mpg!
http://www.dieselmotorcycles.com/models.htm

[Matra et Alpine]

Diesel motorbikes are the future, 100mpg!
http://www.dieselmotorcycles.com/models.htm

Been around for 102 years
http://www.peace65.freeserve.co.uk/P...s/timeline.htm
More mainstream since the 50s.
I've got a vid of an East German/Czech diesel that was at the Isle of Man a couple of years back., You could hear the engine ( not exhaust ) from about 1/2 a mile and the rider looked as if his eyeballs kept bouncing up and down even after he stepped off

[henk4]

Diesel motorbikes are the future, 100mpg!
http://www.dieselmotorcycles.com/models.htm

outdated technology there, indirect injection. Max power at 5700RPM? Max torque at 4200 RPM? Maybe they should put a Smart 2 cylinder CDI engine in there.

[h00t_h00t]

Its a diesel, and built mostly for economy and reliability, which low revs love.

[johnnynumfiv]

The corvette shuts down 4 cylinders on highways to get that 28 mpg, its not all gearing.

[Doza]

The 5.3 V8 found in trucks and MC/Ipala SS's is the one with DoD. Also found on the V6's of the MC/Impala.
http://www.gm.com/company/gmability/...od_050803.html

[henk4]

Its a diesel, and built mostly for economy and reliability, which low revs love.

A diesel as such does not mean maximum economy. this one is fitted with an injection technology that gives at least 20% less economy than a modern Direct Injection Diesel. Furthermore 5700 revs is amazingly high for a diesel and a max torque at 4200 rpm is even worse. My car's max torque sets in at 1750 rpm.