Jet-A-Vator carb grid.

[Isaac Zackary]

Wow! I like VW history! I didn't know VW had a side draft carburetor either. I did know the Type III had EFI optional since 1968.

Yes, I plan on an oil heater, plus 0W-30 durring the winter. I'll be driving from -40°F (-40°C) up to 115°F (46°C) and 12,000ft above sea level down to sea level.

Yes, intake manifold pressure (or vacuum, depending on how you look at it) is dirrectly related to engine load. At full load in a naturally aspirated engine the intake manifold runs at just under ambient pressure (practically no vacuum). Yes, you can measure pressure in each cylinder individually with special spark plugs with pressure sensors. Also the air density between the spark gap can change the impedance. But for practical purposes it's easier to measure intake manifold pressure or mass air flow. Throttle angle also kind of works but isn't as precise.

[Isaac Zackary]

Don't get me wrong about water injection. To have water injection would be a dream come true for me.

[freebeard]

If I don't respond it's probably because I have nothing to add.

There was a time I was thinking about building a 36hp engine that had a crank-fired ignition sensor hidden in the bottom of the fan [belt lower] shroud and a gutted 28PICT that is nothing but a throttle body, with a fuel injection nozzle in hidden in the air cleaner.

...nothing on topic anyway.

[2009Toyotoad]

Originally Posted by jakobnev

Tin cans, nail, hammer.

Yep! Put this on the pile of the intake vortex generators, and home built hydrogen generators.

Put your money into a high precision wheel alignment, a quality tire gauge, or even a fresh wax job and the money is better spent.

I'm sure the website has some testing data to indicate, "it really, really, works!"

This isn't nascar and it sure looks like pure Hokum to me. Perhaps if I rub the magic crystals more vigorously the merits of the product will be believable, but I doubt it.

[Isaac Zackary]

I know this looks like pure engine mythology, but the website doesn't have any test data. The test data was done by other companies.

Anyhow, the problem with a carbureted or throttle body engine is that the air/fuel mixture has a long way to go before reaching the cylinders. That allows the liquid fuel droplets to colect and fall out of suspention, which creates large unburnable droplets of fuel. Carbureted and throttle body (even port fuel injected engines to a degree) use intake design and heat to help atomize the fuel. For an example, a lot of guys go try to get better power, and sometimes think the'll get better fuel mileage too, by putting on larger diameter intakes and by porting and polishing the heads. The fact is that the larger diameter slows down the intake charge velocity which allows more fuel to fall out of suspention. And the polished surfaces don't help fuel that's fallen out of suspention to reenter the air stream.

Heat is another factor. Ideally, the whole intake charge would be one homogenous gas (ya, ya, I know, then there's the not so fully homogenous stratified charge). On a lot of engines, the hotter the intake manifold is the richer the O2 gauge reads. Not that it's running richer, it's still pulling the same amount of fuel and air, but it's evaporating more fuel so more fuel burns and takes out more oxygen out of the exhaust. So therefore the O2 gauge reads richer.

It's obvious that surfaces do matter. I don't know if this thing really will help being it's so close to the begining of the intake. Supposedly it should help create smaller fuel droplets and add more heat to the fuel. I have thought of maybe instead taking copper plates to use as intake manifold to head gaskets and cutting a jagged edge on the inside to promote flinging fuel drops back into the air stream. One guy I know cuts a ledge around the intake port just before the valve seat for the same reason.

[RustyLugNut]

Originally Posted by 2009Toyotoad

Yep! Put this on the pile of the intake vortex generators, and home built hydrogen generators.

Put your money into a high precision wheel alignment, a quality tire gauge, or even a fresh wax job and the money is better spent.

I'm sure the website has some testing data to indicate, "it really, really, works!"

This isn't nascar and it sure looks like pure Hokum to me. Perhaps if I rub the magic crystals more vigorously the merits of the product will be believable, but I doubt it.

A bit more thought and on topic discussion would be a courtesy - weather for or against.

Isaacs rebuttal is a goodly read.

[2009Toyotoad]

Originally Posted by RustyLugNut

A bit more thought and on topic discussion would be a courtesy - weather for or against.

Isaacs rebuttal is a goodly read.

While I agree Isaacs rebuttal is much more detailed. the device appears to be the same quackery that spins around every time fuel prices jump for an extended period of time.

The cynicism in my response, was more from the prospective of having purchased and used many of these types of devices in the past and the wishing that others avoid making the same exact error.

While we can disagree whether my response was merited, Why is one more detailed response better than a lesser and, yes, glib, response? isn't there room for all points of view or writing style of responses?

[RustyLugNut]

Originally Posted by 2009Toyotoad

While I agree Isaacs rebuttal is much more detailed. the device appears to be the same quackery that spins around every time fuel prices jump for an extended period of time.

The cynicism in my response, was more from the prospective of having purchased and used many of these types of devices in the past and the wishing that others avoid making the same exact error.

While we can disagree whether my response was merited, Why is one more detailed response better than a lesser and, yes, glib, response? isn't there room for all points of view or writing style of responses?

They provide little to no information. So why post? If you have no insight on the technology, the inclusion of "opinions" buries the discussion.

To be truthfully honest, this carb grid and items you mentioned such as the vortex generator and HHO devices can work in a narrow window of applications where the engine is far from optimized. There is nothing magical about it.

Vortex generators do work on older engines with "lazy" combustion chambers such as the old Hemi engines. A reduction in emissions and a slight increase in torque output at partial loads is the result, but along with this comes lost peak power as the vortex generator becomes an impediment at higher air flows. Modern engines already have tumble and swirl designed into intake and port configurations and will not benefit from these vortex devices.

HHO generators is a sticky subject on these forums due to the lack of understanding of a branch of industrial chemistry. On other scientifically moderated forums, many have concluded it is a plausible pathway to improved combustion via the seeding effect of precursor radicals if a very narrow set of conditions exist. However, the gains will only be in the few percent range in a stoichiometric mix.


Carburetors, by their very nature, have had numerous devices and circuits hung on them over the years to coax more power and efficiency out of what is essentially a very difficult proposition - fueling an engine over a broad band of loading conditions. I have on my workbench an old Carter ThermoQuad with electronic feedback and an old Holley Spread Bore with a custom air bleed plate underneath the primaries so that the carb could be used with an oxygen sensor feedback. Both carburetors approach the pinnacle of carburetor design and though I am sure fellows like OldMech can rebuild them in their sleep, I would rather have a few injectors and a handful of sensors and wire to deal with as found in modern engines. Earlier carburetor applications had "holes" in their operation that a carb grid could help. But, other devices could help just as well if not better. Holley had a set of high shear nozzles that increased fuel atomization as well as the availability of aftermarket sleeves that increased the vacuum signal across the nozzles with a slight loss in top end air flow.

All the above Isaac probably already knows, but someone looking for information can glean keywords and concepts to continue their investigation if they so desired. Saying " this stuff is all bunk", does little to help anyone.

[freebeard]

I have thought of maybe instead taking copper plates to use as intake manifold to head gaskets and cutting a jagged edge on the inside to promote flinging fuel drops back into the air stream.

Why not an electrically heated Jet-A-Vator? WAI is Ecomodder canon.

Originally Posted by 2009Toyotoad

The cynicism in my response, was more from the prospective of having purchased and used many of these types of devices in the past and the wishing that others avoid making the same exact error.

Do you see what you did there? The question of the merits of this commercial product is only similar to the question of this concept, let alone totally other things you may have tried.

On thing to keep in mind about this is the name, Gene Berg. FYI, he and his son Doug were legendary on the drapstrips of Southern California for decades, going toe to toe with the best. They were doing something right.

Testing was done by HotVWs magazine. The Mileage Motors series was one of their most popular and ended all too soon. From memory, the only single change that made as big a difference was the freeway flyer transaxle.



The Berg's claim of 40% increase isn't tenable, but the tested 10% is, although it's buried in re-jetting of the main jets and added ignition advance. But the philosophy holds, give a little to get a little—top speed is down, but bottom end torque is up, with improved mileage.

Edit: Poking around of the CB Performance site I found this:

CB's Black Box
Is it possible to combine performance and good mileage? It is with CB Performance's new easy-to-install electronic package.


I remember reading about this at the time and ignoring it because the software is tied to the Windows OS.

For example, with our settings we cruised along at 3,200 rpm (approx 70 mph) with the timing at 45° for maximum mileage, but the moment we stepped on the throttle the vacuum dropped, and timing dropped with it to 30° to prevent detonation - the best of both worlds! And the second mileage test, over the same highway and at the same gas stations, proved that the engine like it, as it improved to 31.66mpg, an increase of 3.43mpg, or 12.15%.

[BLSTIC]

Thread Revival!

Looking at this thing, it functions purely as a vaporisation aid. The restrictor part of it has nothing positive for economy and is an all-round negative, but necessary for the product to work

What it does is that via the restriction it creates massive airspeed, this would tend to rip apart any droplets of fuel as they accelerate (and elongate) with the air to go through the tiny holes. On the other side, once through, you would get huge turbulence as the now super-high-speed air mixes with air that is hardly moving (being hidden behind the plate and not the holes), this further breaks down and evaporates the fuel. This turbulent zone would not last long (because of the small spacing between the holes) and you would then have uniform airflow with much more vaporized fuel than earlier. You will probably also have a more uniform spread of rich/lean areas because that's the nature of restrictions, some air flows to the next restriction rather than through the first one. It's why air cleaners that have some tiny restriction can improve airflow through carbs by making it uniform.

However I would say that the effect is to improve the horrible vaporisation of, say, webbers, rather than an all-encompassing magic carb gadget. I would doubt its ability to improve, say, an SU that had been modified for improved fuel shear or anything with a stepped annular discharge booster venturi on a small diameter primary venturi (both situations already have ultra-high airspeed and good distribution at the fuel discharge point, and both have been noted to generate a 'fog' rather than any visible droplets)