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cwtnospam 02-16-2008 07:06 PM

Quote:

Originally Posted by wdympcf (Post 451632)
At 165kW (221hp) in a 2-seater roadster, I don't think I would classify the Tesla Roadster as being particularly environmentally friendly. The energy still has to come from somewhere!

It can come from solar, wind, and hydro power, all of which are much better than any internal combustion engine. No two seat sports car is ever going to be as environmentally friendly as a family sedan using the same basic technology, but the Tesla is far more environmentally friendly than an SUV. Even a hybrid SUV can't compete with Tesla's all electric sports car, which according to their site gets the equivalent of 135mpg!

Edit: It's important to note that you won't get the equivalent of 135mpg while doing 0 - 60 in under 4 seconds. ;) Drive it like a normal car though, and you're sure to use less energy than even the best hybrid.

Phil St. Romain 03-05-2008 02:08 PM

Anyone know if this technology is for real?
- http://www.preignitioncc.com/us/index.htm

Quote:

Our scientific testing has led us to believe that the PICC will increase the mileage of all personal vehicles to over 100 miles per gallon (city or highway).
Sounds too good to be true! Watch the video, if you have time.

If there's something to it, then we ought to expect it to show up as standard equipment in more and more vehicles, it would seem.

fazstp 03-05-2008 03:07 PM

A quick Google came up with lots of advertising and lots of questions but not much independent testing.

Might be a wait and see.

aehurst 03-05-2008 05:14 PM

Similar claims were being made for modifications back in the 70s... basically took the fuel line and wrapped it around the exhaust manifold a few times before the line went to the carb. Claim was it would heat the gas to vapor, which would burn more efficiently and thus increase mileage. Never caught on.

This seems to be doing the same thing... i.e. heating the gas to vapor before burning.

I'd definitely wait and see. At best, I think the claims are wildly exaggerated.

Sherman Homan 03-05-2008 05:26 PM

That might have worked with a carburetor, but you can't pump vaporized gas through a fuel injector. And even more silly, the article describes it as converting the gasoline to a plasma state. Which means that super-heated gasoline would somehow be introduced to the intake manifold in the presence of oxygen... Now that would be fun to watch!
From a distance!

fazstp 03-05-2008 06:47 PM

They have a list of EPA tested devices on this site, with many similar to the PICC, none of which measured up to their claims.

Gasoline-saving products & devices

iampete 03-05-2008 07:50 PM

The bottom line is that there is only so much energy available in a gallon of gasoline if one chooses to consume it in an internal combustion engine. The causes of efficiency loss are quite well known, and current engines are not that far from the efficiency that technology allows within the constraints of providing what the industry thinks that consumers are willing to buy. As dumb as the auto industry has tended to be, they are not that dumb.

While it is certainly possible to optimize things around the edges by improving efficiencies related to mixture, or ignition, and such, improvements of this type tend to be incremental, i.e., on the order of fractions of a per cent, or, at most, a few per cent.

I find any claims of dramatic efficiency improvement, e.g., tripling or more of current mileage as in this case, hard to swallow. Confirmation of claims like this via a controlled test from reputable, independent sources would obviously be sufficient to reconsider my skepticism, but I don't think those confirmations will be forthcoming any time soon.

NovaScotian 03-06-2008 09:50 AM

I agree with Pete. The efficiency of a gasoline engine is related to the combustion temperature of the fuel which is primarily a function of chemistry, the cooling water temperature, the compression ratio of the engine (which is why Diesel wins and superchargers work -- increasing the pressure in the cylinder increases the combustion temperature), and a few other details. Preheating the fuel would have negligible influence on any of them.

J Christopher 03-06-2008 12:57 PM

Quote:

Originally Posted by aehurst (Post 456231)
Claim was it would heat the gas to vapor, which would burn more efficiently and thus increase mileage. Never caught on.

This seems to be doing the same thing... i.e. heating the gas to vapor before burning.

Without a completely sealed fuel delivery system, I don't see how it would work. Vapor lock is not generally considered a good thing.

Phil St. Romain 03-06-2008 03:32 PM

Seems the jury finds PICC to be a hoax?

I'm not competent enough on this topic to reply to the criticisms made by some of you. I hope you've at least looked at the video and not responded to what you "think" they're saying. There are testimonials on the site from users and mechanics. Might be phoney, I know, but you can buy the kit and have it installed with a guarantee of 50% increase in fuel efficiency or your money back. You don't usually see hoaxers doing that.

Should it turn out there's something to this, it would be a good stock to own. :)

Sherman Homan 03-06-2008 03:52 PM

Phil, go back to their site, there are two parts to this process. The first part is the Hydro assist, the second is the PICC. The PICC isn't even designed yet! They haven't built one of them.

The Hydro assist part is a hydrolysis converter that separates water into hydrogen and oxygen then feeds the two gases into the intake manifold. This is insanity for two reasons: it takes energy to split water molecules, that energy comes from the car's engine and you can't get more energy out of a system than you put into it. It will decrease gas mileage, not increase it!
The second reason is safety, hydrogen and oxygen love to combine in the presence of heat, electricity or even sufficient physical motion. An intake manifold is perfect for all three.

iampete 03-06-2008 04:27 PM

Quote:

Originally Posted by Phil St. Romain (Post 456421)
Seems the jury finds PICC to be a hoax?

I'm not competent enough on this topic to reply to the criticisms made by some of you. I hope you've at least looked at the video and not responded to what you "think" they're saying. There are testimonials on the site from users and mechanics. Might be phoney, I know, but you can buy the kit and have it installed with a guarantee of 50% increase in fuel efficiency or your money back. You don't usually see hoaxers doing that.

Should it turn out there's something to this, it would be a good stock to own. :)

Just for the hell of it, I did sit through the video. Based on common knowledge physics and chemistry, there are fundamental flaws with the concept as described.

The most obvious one involves the claim that water is broken down into hydrogen and oxygen in the converter and is then burned in the engine. Firstly, it takes a non-trivial amount of energy to dissociate water. This energy has to come from somewhere. Simple thermodynamics tells us that the usable energy produced from the "burning" of the hydrogen (btw, oxygen doesn't "burn" but is combined with the hydrogen) will be less than the energy required to produce it in the first place.

If I were on a jury, and absent controlled test results from reputable, independent sources to back this up, my vote is that it's pure BS. In my view, the bottom line is the old "there ain't no such thing as a free lunch" principle.

I take the refund guarantee the same way I take the "guaranteed to make big money in your spare time" schemes so common on the internet today.

Edit: Sherman made the main point while I was wasting my time watching the video.

aehurst 03-06-2008 04:28 PM

Quote:

Originally Posted by J Christopher (Post 456385)
Without a completely sealed fuel delivery system, I don't see how it would work. Vapor lock is not generally considered a good thing.

Vapor lock was a common occurrence in 60-70s US autos if one drove in hot weather and in particularly high altitudes such as Colorado and western New Mexico where steep grades were the norm. The simple solution was to pour a coke bottle of cold water over the fuel pump and let it cool a while, which worked every time. In these cars, the fuel pump was mechanically driven by the engine and was bolted to the block near the bottom.... a good five feet of line before it got to the carbs. Being bolted to the block, the pumps were always at risk of getting too much heat if the engine was running hot.

Never put the system on one of my cars, so can't say for sure vapor lock wasn't a problem for those who did. Had a couple friends who swore the system worked.... in Kansas.

NovaScotian 03-06-2008 06:13 PM

Ahh yes -- pour cold water on the cam-driven, short-block-mounted fuel pump only a short distance from the radiator; brings back memories of actually sacrificing a cold can of beer to that purpose on a boat engine. Those fuel pumps were the ones that occasionally ate the fuel pump membrane, and where changing it was such a PITA.

aehurst 03-06-2008 07:58 PM

Quote:

Those fuel pumps were the ones that occasionally ate the fuel pump membrane, and where changing it was such a PITA.
Yeah, changed a couple of those out. If you're doing it alone it was a constant getting out from under the car to tap the ignition one more time to get the cam in the right spot so you could slip the pump in and bolt it down. It was a big time chore.

Even though some of my friends thought the pre-heated fuel thing worked, I was never convinced. Having overhauled a couple of the old Chevy Rodchester carbs as a kid, I knew the carbs worked basically like a toilet... engine sucked gas, the float would drop opening a valve and more gas would run into the bowl for the engine to suck out. Just like a toilet... and I just couldn't understand how that float would work with a vapor (suspect it didn't). :)


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