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Accelerating slowly, particularly in small petrol engines is not the most fuel efficient method of accelerating.

See: http://www.autospeed.com/cms/article.html?&A=112611

The most fuel efficient method to accelerate to a given speed that you will then hold for a long period is to use as much throttle as possible without triggering specific "wide open throttle" ECU fuel mappings. (This will over fuel). In most cases this means 50-75% throttle.

I like Chalnoth, he seems to know whats going on. At the very least, I concur with everything hes said. The 'wall of sound' idea seems like a bit of a wives tail constructed on a way to deal with tinitis, which does involve using brown or pink noise to eliminate 'perceived' noise in the ear-drum. In reality, however, if you try mixing an audio track with noise, the output is an audio-track mixed with noise. You might be able to do something more obscuring if you multiplied the carrier wave (street noise) with the white noise track, but that would require a lot more control over your environment than you appear to presently have. I have personally tried this approach by playing really loud music, but I find after the first 6 hours you have only managed to accomplish two things. 1) pissing off the neighbors, and 2) annoying yourself with your own music playing so loud you can't think about anything else.

Sound waves don't like vacuums and insulation. So, you will need to identify the source of your noise leak - use a sound meter. The description of your house is a little bit rubbish, but if it has wooden walls, your sound is probably haemorrhaging there. I would be looking at something (not specifically) like http://autospeed.com/cms/title_Fitting-Sound-Insulation/A_109796/article.html as its specifically looking at insulation used for shielding against car frequencies. You would need to line the walls with something like this. Roofs are often fairly well insulated, and assuming no audio gets into the room, you shouldn't need to carpet all the walls. Thats more for dealing with internal reflection, although in a worst case it will deaden any echos from audio getting in. Depending on the size of the room, active audio cancellation is very tricky. It works well for audio cancelling earphones where the system knows where your ears will be in relation to incident noise, however synchronizing destructive audio patterns for an audience in an unknown co-ordinate is nearly impossible.... unless you are lucky enough for all the noise you care about to be coming from a single-point source.

Amazing density of false claims.

Now, I can't call your views on aesthetics "false", mind you, but I can point out that the whole point of Aptera was that a particular persons idea of what a car "should" look like should not dictate what this vehicle looked like. They took vehicle design back to square one: "How can we carry two people and cargo using the absolute minimum of energy without compromising safety?" Everything flowed from that. If the most efficient vehicle shape to achieve that goal was a giant pig's nose, then the vehicle would have looked like a giant pig's nose.

The vehicle does not have a "plastic body". It has a "composite body". If you don't know the difference between the two, you really owe it yourself to at least look up what composites are. The strength in a composite comes from a fiber matrix ; the plastic resin that's injected is simply a bonding agent which defines the shape and transfers any forces into longitudinal stress on the individual fibers. Hence, stress on a composite is really tensile strength, which makes them very hard to damage. Ever seen pictures of one of those 100+mph wrecks of a composite supercar where the car is in pieces but the driver walks away unharmed? That's what composites do -- they either don't break at all or they shatter, but in the process they absorb tremendous amounts of energy compared to their mass. A nice side effect is that you can never get pinned into a composite vehicle; they don't irreversibly deform.

Three wheeled vehicles have not "always failed in the marketplace". If you want a present example, the Can-Am Spyder has been doing very well. Most of the difficulties of three-wheelers in the US are regulatory anyway. You can't have a three-wheeler that weighs more than (depending on the state) 1500-1800 lbs, to name one.

Stability is not in the least compromised.

I'm not sure how you define optimum, but it sure as hell isn't safe.

False. Tadpole-configuration with the CG just behind the front wheels is just as safe as a conventional four-wheeled approach (unless you're driving backward at high speeds).

This is so different, will we need special licenses/training for it?

Why? You don't need a special kind of license to drive stick vs. automatic. A license doesn't test for your ability to use the controls, it tests for your ability to do the right thing with the car features at the right times.

Early cars didn't have steering wheels, and if the vehicle was street-legal you wouldn't need a special license today to drive one

Bet you $100.00 that swapping your Beloved K&N to a new paper filter will cause the same increases.

also changing your overpriced plugs to regular iridium plugs will do the same.

It has been proven time and time again in automotive trade magazines and other places, the filter and spark plugs are NOT restrictions in performance. 99% of everyone that "feels" a difference needed to do the basic maintenance anyways.

you CANT benefit from a K&N filter unless you increased your engine displacement by 60% and did not upgrade the intake.

http://autospeed.com/cms/A_107824/article.html these guys proved that the air filter makes NO difference.

If you want to cling to your marketing, then switch to royal purple oil and add a spiral air insert along with a fuel line magnet.

Not calling you dumb, just letting you know you bought a bunch of snake oil that is doing nothing that normal parts would have done.

Apparently where you come from, the position of the wheels and the location of the center of gravity is irrelevant, and all that matters is wheel count.

Meanwhile, back in the real world....

Oooh, is it anecdote time already? Well, then, this car has shown how unstable 4 wheels are, this car has shown how gasoline cars are inherently unsafe, and this person has shown how white people are cannibals. Gotta love how that works! ;)

FYI...

(Yes, I know you were kidding... but it's a popular misconception, so I thought it should be addressed)

This is very interesting technology. These solar races really produce odd looking vehicles. Three wheels makes sense in terms of rolling resistance, but I can help but think what might happen if it needed to take a turn fast.

Just because it's three wheeled, or because it's this specific car? Three wheelers can be extremely stable.

I've always wondered how much power could result from the sunlight hitting the roof of my car all day long when I'm at work. Seems like there is potential missed opportunity there.

The missed opportunity would be to put those precious solar cells on top of a car where you have to carry the weight around and the angles are poor rather than on a rooftop where you don't have to haul the weight around and where they can be positioned at an optimum angle.

Now, the info on safety is a little sparse from my quick look at Aptera's website, with the faq saying "It will match other commuter vehicles". Faq here. Safety Here

The old version of the website was more detailed; it's kind of in transition right now. Yes, they have a full compliment of airbags, ABS, etc. Crash testing has been modelled by the same software BMW uses. It's a layered composite, like exotics (ever seen an exotic wrecked at 100+ mph, and the driver walks away? Composites are great that way). Here's a copy of an article whose author was introduced to the Aptera by its manufacturers handing them a sledgehammer and letting them wail on a shell. They nearly knocked their teeth out on the rebound and couldn't even scratch it. Roof and door crush strength have been reported to be over double the NTSB standard for cars.

First up is the single back wheel. Won't that make the vehicle a rollover hazard?

No. Here's excerpts from a great Road and Track article on the subject of three wheel stability. Net results of their testing of various delta (one-wheel forward), tadpole (one-wheel backward), and four-wheel vehicles? The deltas were always prone to oversteer and rollover, and no amount of tuning could change that. The tadpoles, like four-wheelers, were prone to understeer -- even a bit more than the four wheelers -- and were just as stable. Plus, they had a lower moment of inertia, and thus had a faster reaction time. When you think about it, it makes sense. When you brake, your CG shifts forward, putting it between the wide front stance. There's not much weight on the backside of a four-wheel vehicle when braking/turning.

I presume the front wheels are extended to help mitigate this issue, but one good blowout looks like it could send that sucker fishtailing right into roll. (And for that matter, how servicable is that tire?)

The panels on the side come off. Same with the front wheels.

My second issue is the power-train. Generally you want as much weight sprung as possible, and electric motors are heavy. Aptera seems to understand that as it appears there is an axel linkage on the front wheels. Presumably this is how power is transmitted.

Correct, except for the "electric motors are heavy" part. Electric motors are exceedingly light for how much power they produce. Batteries are heavy.

Is having that axel exposed going to cause any safety and reliability issues?

Driveshafts are typically exposed on the underside of a 4WD vehicle, right where rocks are getting kicked at them. Anyway, if there was any problem, they'd just shroud it.

Could'nt the steering be accomplished by swiveling independent pods rather than linking them?

The pods do swivel. The entire front of the car doesn't turn at once. There are CV joints at the wheels.

It should also be noted that it's been reported that the batteries are mounted low, as is the passenger seating, so your CG is low. Anyone who's not familiar of the gains of mounting batteries low should take a look at videos of a Commuter Cars Tango ;) Tall, narrow little vehicle, looks like the most unstable thing in the world, yet it barely budges side to side on turns.

First off, I can't recommend strongly enough that you view the YouTube video of Chris hitting the shell with a hammer. It has over double the required roof and door crush strength for cars. It has not just an ordinary crumple zone, but an innovative crumple/deflection zone designed to help the vehicle ride up in an accident. It has full in-seatbelt curtain airbags. This is a vehicle that should blow most cars out of the water when it comes to safety. Secondly, as for handling, you need to read more about three wheelers; here's a primer. One wheel in front and two wheels back is notoriously unsafe and unstable, but two wheels forward and one wheel in back, with the CG just behind the front wheels, handles almost identically to a four wheel car, except that it has a faster response time. Basically, when you brake or steer, the CG slides up between the two front wheels, and thus has the same amount of resistance to flipping laterally that a four wheeler has. Also, they are naturally prone to understeer (like four wheelers), not oversteer (like tadpole three wheelers). About the only thing you wouldn't want to do in a tadpole three wheeler is something like a J-turn.

There are many reasons for going with three wheels. Yes, a big one is that it has a lot less certification that has to be done. But if they're voluntarily doing crash and crush tests, who cares? The other benefits are numerous; here's just a few. The ideal aerodynamic shape to enclose as much volume as possible with as little drag as possible is a stereotypical teardrop (or truncated teardrop); this means wider in the front than in the rear (hence, two wheels forward, one backward). Three wheels means you can elimiante an entire wheel. And all of the drivetrain/braking/cabling/wiring requirements that go along with it. Which reduces weight, purchase costs, and maintenance. And cutting weight means increasing range, and so on down the line.

Quite true, so long as the CoM is positioned just behind the front wheels. When braking, that puts the CG directly between the front wheels. You're left with the same resistance to rollover, but you have a lower moment of inertia, so it's more responsive. Also, with two wheels at front steering, just like in a normal car, you have similar tendancy toward understeer rather than the extreme oversteer of "delta" trikes.

There was a good article from Road and Track in May 1982 where they tested various configurations; there's excerpts here.

I haven't yet run into a person who is neutral about the Aptera's styling; I find about a fifty-fifty split of "Uck! That thing is hideous!" and "Wow, that is the neatest looking car I've ever seen!"

As with all cars, if you damage a part of the car, you pay to get it repaired. No different with an Aptera. You damage a wheel pod, you pay to get it fixed. Aptera is hardly the first car to have exposed wheels. As for three wheelers, there's a big difference between delta and tadpole configurations.

I'm cheering for Aptera not just because I'm in line to buy one (indirectly, through a California intermediary), but because technologically, they really deserve it. A drag coefficient of only 0.11 (Prius=0.26), combined with a low cross-sectional area -- i.e., they let physics dictate the shape. Speaking of the shape, it's an inverted wing, so more downforce the faster it goes. That, combined with a wide (~7 foot) front wheelbase and low-mounted batteries for a low CG, lead to strong stability against rollovers. The design is a tadpole trike for stability, weight reduction, and drag reduction. Long 45" crumple/deflection zone, in-seatbelt airbags, with roof and door crush strengths double the NTSB standard. Composite construction for light weight and safety (stronger than steel). Lithium phosphate batteries, which should last the life of the vehicle. The ridiculously low drag and rather light weight approach allows them to use only 10kWh of batteries, meaning faster charges, charges on only wall current, lower potential maintenance/repair costs, and a whole host of other benefits (uses only 80Wh/mi @ 55mph, 140Wh/mi @ 85mph). I could go on for hours; it's an impressive piece of work. I'm simply not as impressed by the other contenders.

Oh, and they recently brought on the head of production for the Ford GT, Dodge Viper, and half a dozen other high end cars to head up their manufacturing. First cars go out the door this December; mine should be late next summer. Can't wait!

Just as a follow up - AutoSpeed is running a great article on BSFC or Brake Specific Fuel Consumption.

AutoSpeed - Brake Specific Fuel Consumption

I highly recommend this to anyone interested in how different operating conditions affect fuel economy.

BSFC is the measurement of how much power vs how much fuel in consumed - basically measuring how efficient an engine is. In an ideal world you'd have an electronic throttle and a CVT. The throttle would directly translate into how much power you are requesting. The ECU would use a BSFC map to determine the most efficient engine RPM and throttle body position to generate that power and the CVT would allow you to maintain that RPM for as long as you are requesting that power level.

Allow me to also recommend http://www.autospeed.com/cms/A_2936/article.html from an Australian automotive site. The author is attempting to build a recumbent human-powered vehicle from scratch. So far he's detailed frame design, prototyped front and rear suspension, all the while explaining his selections and describing alternatives. Even if you are not excited by cars, the site is worth a look for articles such as the recumbent bike, and general tech articles about making things, or re-using junked technology to make other cool stuff.

I'm doing this myself now. I'm still in the early stages but have most of the parts. Just need to pick the computer itself and the power supply. (Probably go Opus with a ITPS)

It's definitely going to be linux. I think I'm going to just put a half tower in the trunk as I'm going to need a lot of expansion cards.

I'm leaving the gauges in place and putting the monitor (lilliput 8" touchscreen) in front of it and wrapping it up in custom fiberglass cowel.

My wiring passes through the gauges into other systems, for instance the battery charger so it's easier to leave everything in place and easier to just remove screen and replace with stock cowel for inspection time. ;)

For the harddrive, I'm using a ruggidized harddrive designed for automotive use. Slow but it's got a great temperature range and shock rating.

The keyboard I'm using is a tiny one I found on ebay. I cut it down to fit in a 1 DIN position. It fits between the stock radio and AC controls. You don't know it's there when retracted.

Most of the inputs will come from OBD-II (elmscan that I embedded inside floor) but it's not fast enough for the tach and speedo. (4 samples a sec at beast ISO) I'm tapping the tach, speedo and a few other input signals directly and processing them with a PIC. The PIC will then communicate with the PC via serial.

I'm thinking later, I'll add a large commodity drive for other non essentials that will be activated via a temperature controlled relay. So if it's under 40F in the trunk, it won't power the harddrive until it is hot enough or maybe I'll just use a USB drive.

My first advice is to buy the factory service manuals on ebay. They are invaluable. I got mine for $40 US. Three phone book size volumes with schematics as well.

You might find the factory training books for the electrical and whatnot as well. I did. It was nice to have the whole ECU protocol detalied. (Though not planning to tap into it at this point)

If possible, buy extras of whatever your going to mod on ebay. For most parts I'm fooling with, I have 2 or 3 extras that I've amassed over time. If your patient, you can get stuff cheap.
For instance, in my spare room, I have a spare dashboard, gauges and most everything else on the dash. I'm using this to work on the fabrication so I don't have any downtime (or screw up my car)

$1700 dollars worth of stuff righ there. $240 shipped in mint condition. Patience is the key.

As far as the legality, I'm not concerned. If I had a massive failure, the only thing that I would be missing are my current speed, engine rpm, fuel and oil temperature. Nothing that would ever cause a crash. I can estimate the first 3 fairly accurately. Certainly enough to safely pull over and remove the screen and use the OEM gauges. A fuse could do the same thing to the OEM gauges (and has to me before)

Besides the fact that I'll have more readings on my car (which will actually improve safety), In phase 2, I'm going (try) to tap the ABS wheel speed sensors. By using the four sensors, I've now added differential tire pressure monitoring to my car.

My whole design goal is to have something integrated, yet I want it stealth. If you walked by, you'd have no idea it was anything special. You might if you were astute, notice the monitor, but you would probably just mistake it for a regular an OEM readout.

A great site (Australian cars though) for technical car info and ideas is Autospeed.com.

There is some other stuff, but I'm not going into detail until it's done :)

Check out This page
for instructions on how to build your own vehicle immobiliser. It features a warning LED, kill switch, and magnetic pickup to deactivate the system.

New?! Concept cars are nothing new.

Aseries of 120 of them were s'pose to be built but in the end only 5 were built, but Volga Shipyard still has all the jigs 'n drawings, etc & will build more to order.

The Orlenok page on The WIG Page site

The Orlenok page on at autospeed.com

Some pics:

http://www.airforce.ru/aircraft/ekranoplans/Orle no k.jpg

http://www.airforce.ru/aircraft/ekranoplans/orle no k4.jpg

http://us1.webpublications.com.au/static/images/ ar ticles/i13/1306_5mg.jpg

http://www.se-technology.com/wig/html/image.php? co de=0&id=413

"Not to mention internal windshield wipers."

Oh that is sick dude, hahaha.

You'll need a set of these too.

GM has a long history of making really sweet concept cars, but by the time they are actually produced, somehow they get turned into "your father's Oldsmobile." For example, compare the Olds Alero concept with the production model. See what I mean? All these nice ideas that GM engineers are teasing us with will not come to pass. They're going to make an ugly SUV out of it by the time it gets to us. Leave it to another company to turn the concept into the actual production car without pandering to the lowest common denominator.

There was such a thing!

Software called Kalmaker (www.kalmaker.com.au) was written that gives you access to nearly every function of GM Delco ECUs. This ecu was used on a wide variety of cars, from 2 litre 4 cylinders to 5 litre V8's.

In Australia, where the software was written, the ECU was mostly used on the Buick 3.8 V6, from 1989 to 1997.

Previously, it was available in a low cost home user version, but is now available only in workshop versions, for around US$600. ECU's themselves are also available, or can be had from wreckers. Many project cars of many and varied configurations have used the re-programmed ECU's to great effect.

However - the original author never recovered more than a fraction of his time and effort, and the right to sell Kalmaker has passed through many hands and liquidation sales. Even at prices much less than programmable ECUs, there's apparently not a large enough market to sustain such a thing.

Additionally, if you're interested in a more rational approach to car modifications, allow me to heartily recommend Autospeed. Well worth the very low cost, and there's a large number of free articles. A wider ranging Tech Journal, that should be of interest to Slashdot readers will be launched soon... I'm excited.

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

80% the length of a 747 but fater. Only the 1st 4 were built. Volga shipyard's still got or the jig 'n stuff & will build more to order.

Here's a good article on them.

Here's a close up pic, notice the twin 23mm cannon dorsal turret

Here's a pic of 2 flying along side by side

Here's a rear 3.4 view

Top view

Front on, on its beaching bogies

Unloading a armoured fighting vehicle

On the tarmac

3 way drawing

I heard of this kind of thing many years ago.

The Soviets were way ahead of the game in this area as long ago as the 60's, they were called Caspian Sea Monsters because they were tested in the Caspian Sea, and looked like neither plane, nor boat.

This web site has a very nice detailed article complete with many photos.

They were quite the strange beasties back then, heres another look at them.

And heres the WIG site (WIG is an abbreviation of Wing In Ground-effect), which is also a nice comprehensive resource about these interesting vehicles.

The model maker Revell even made a plastic model kit of one, some years ago.

Apparently, this type of aircraft hasn't found it's commercial niche yet, but it looks like this new application might work.

I love hacking cars. Saddly here in the USA there is less of a modern-car hacking cultrure. In the USA we've *mostly* got old hot-rodders with carbed V8's, and kids with big-wing/big-exhaust otherwise-stock imports. Not many people are doing MODERN performacne hacking, but there are some.

Many other countries have a real strong culture in this area though. For an example, go to Autospeed, an Australian site where they post weekly articles about auto performance and electronics hacking. Australia is a real hot-spot for this stuff. It doesn't matter that the auto manufacturers are making more complex and advanced products - it just promotes the creation of more brilliant hacks.

If you're interested in programable engine management, adding electonic accessories, etc. all you have to do is dig a little and you'll find a whole world of resources. Just like Tivo, DirectTV, Audrey, or anything else - If you build it people will hack it.