Critique of Aquatune Water Injection System
by Fran Giroux of Hydrogen-Boost.com
The following from hydrogen-boost.com November 2002 Newsletter is posted here temporarily until they post it on their website.
[…] I called for information about Aquatune. I spoke to the tech support engineer who told me that the Aquatune device not only injects water (mist) into the intake but also has an ultrasonic chamber inside that supposedly detaches hydrogen ions from the water molecules, which should aid combustion. I doubted this, relying on my extensive chemistry background.
I proposed to the engineer that any specific ultrasonic frequency designed to break off the hydrogen ions would be difficult to maintain without constant vacuum on the device. In order to do this on a car engine that has a constantly varying vacuum in the intake, a “vacuum reservoir” effect would have to be used, or that at any vacuum setting above a “set” amount would have to be shunted so that inside the device there would only be a lower “set” vacuum effective inside the ultrasonic chamber. The engineer assured me that this is indeed how the unit was designed.
I was also told that the water “mist” exiting the devise was a fine mist, which was actually a mixture of water, water vapor, hydrogen ions and oxygen ions. Once again I doubted this assertion because of my chemistry background. If there were hydrogen ions (positive charge) and oxygen ions (double negative charge) these ions would be attracted and soon come back together. I was told that, given enough time, they would indeed come back together to reform water molecules.
I was told that this is the reason that the device must be located as close as possible to the intake manifold. One foot of hose from the device to the manifold would allow enough time for the ions to reform into water.
I also asked what evidence he had that there was actually hydrogen ions in the mist after the device. It was obvious to me that there was no way to ignite this hydrogen as it was being produced under vacuum. I was told that a test vacuum reservoir was installed in the line after the device (like a large mason jar) through which there could be seen a “blue flame” entering into the jar. This was “evidence” of the recombining of the hydrogen ions and oxygen ions on the way to the vacuum source (intake). I happen to know that hydrogen burns with a colorless invisible flame so the story about the blue flame is questionable to me, though I haven’t tried the set up to confirm or deny the claim.
Relying on the 30-day money back guarantee, I decided to order an Aquatune system and install it on my wife’s Neon which at the moment was not being used as a test bed for Hydrogen-Boost. My wife has been driving this vehicle stock for the last six months with a consistent mileage of 30 mpg, though on the last tank she actually got 31.6 mpg.
Aquatune makes claims of increased mileage of 25% minimum and an increase in maximum power of 15% or more.
I doubted the power claim so I did a pre-installation acceleration test of eight runs, from 10-60 mph. Throwing out the slowest and fastest times I came up with an average time of 11.425 seconds. After installing the Aquatune device as per the instructions I did further acceleration tests and came up with the exact same average time. Obviously an increase in maximum power would cause lower acceleration times, but there was no change in the times.
Examining the “mist” that exits the Aquatune device was disappointing. It was not a mist at all, but droplets rolling alone the sides of the clear plastic tubing leading to the intake manifold.
When the throttle was wide open for acceleration there was negligible vacuum on the device and no water was seen exiting the device. This would explain why there was no change in acceleration times compared to the stock engine. How could there be increased maximum horsepower when the device wasn’t even working at full throttle?
While discussing this with the technician at Aquatune I was told that installation of the intake nozzle, by drilling and tapping into the intake manifold just behind the throttle body, would provide some vacuum even at full throttle, and compensate some for this weakness. The vacuum port I was using on the intake was just behind the throttle body but may not be right out in the strong air flow so it may not draw as much vacuum as the intake nozzle supplied by Aquatune.
I examined the graphs sent to me by Aquatune, of a vehicle tested on 4/27/2001. On the top of the graphs is printed max Power 205 w/o Aquatune, and 229.4 with Aquatune. However examining the graphs themselves shows a maximum power with Aquatune of only 210 hp at 5300 RPM, which is at least slightly higher that the stock 205 but not 12% more horsepower as claimed by the printing on the top of the mis-read charts (2.4% at best). Upon closer examination of the chart over the whole range of RPMs the story is quite different. At the following RPMs the following horsepowers were measured during the test, giving the indicated averages below:
PRM Power w/0 Aquatune Power with Aquatune
4000 183 182
4500 193 190
5000 198 206
5500 203 195
6000 197 176
_________________________________
Average 195 190
So actually the average horsepower over the range of RPMs was lower with the Aquatune device than without it. Aquatune caused a loss of power, not a gain of power as claimed.
Mileage Test
The test vehicle has for the last 6 months consistently achieved an average mileage of 30 miles per gallon, though on the last tank full the mileage was 31.6 miles per gallon. The driving is a mix of city and country roads with some highway miles. The routes each week has been quite consistent, which accounts for the consistent mileage.
After installation of the Aquatune device and performing the acceleration tests I refilled the tank and gave the car back to my wife who went about her regular routine. When it was time to refill the tank after 315 miles, I checked the Aquatune system to see if it was still operating properly. The reservoir was empty so I refilled it and left the engine running, witnessing the continued injection of water with the device. Refilling the tank to the same fullness as before took 10.5 gallons, which calculates to exactly 30 miles per gallon. Hence we achieved no increase in fuel mileage.
After 66 miles into the next tank full I checked the water reservoir to find it only 10% full, so I called Aquatune who told me to adjust the on/off switch to the 6:00 o’clock position rather than the 7:00 or 8:00 o’clock position as indicated in the manual when seeking maximum mileage.
At this position the droplets running down the clear tubing got smaller and there was at least some indication of some mist at the first ½ inch of this clear tubing. Also during repeated cycling of the switch between 6:00 o’clock and 8:00 o’clock caused a barely noticeable change in idle RPM’s. This gave me some hope that there may be at least some affect from the Aquatune on this tank full of fuel.
After another tank full of fuel was used, the mileage was calculated and again came out to be exactly 30.0 mile per gallon, representing no increase in mileage. I removed the Aquatune device, put it back in the original packaging and sent it back to the company for a refund. After a few weeks I had my refund as promised by Aquatune.
Conclusions:
Aquatune does not produce a good mist injection, but rather droplets of water that roll along the sides of the hose on the way to the intake. This is not what a water injection system should do. Adjusting the switch to the 6:00 o’clock position improved this slightly.
There is no “vacuum reservoir” or shunting capability built into the Aquatune devise that would keep the vacuum moving through the device at its optimum “tuned “ vacuum that produces hydrogen ions. Later discussion with the technician at Aquatune verified that the Aquatune device only has a small water reservoir in case of low vacuum during acceleration, but no vacuum reservoir.
There is no concrete evidence that hydrogen ions are being detached from the water molecules as claimed by the manufacturer.
There is no real power increase when using the Aquatune system. Actually there is a slight average power decrease when using the system, when you take into account the whole RPM range.
As a water injection system the Aquatune device, when poorly adjusted, is no better that a small pipe tee that causes a metered, venturi powered, Bernoulli affect dripping of water. A tee can be obtained for a couple dollars while the Aquatune costs $350-$400. Proper adjustment helps some.
Potential problems caused by a poorly designed, or poorly adjusted, water injection system far outweigh any potential benefits. However, I am still on a search for a properly designed water MIST injection system that can bring potential benefits that outweigh the risks. When one is found at an affordable price (less than $100) it will be recommended as a part of the Hydrogen-Boost system, assuming that additional increases in fuel mileage is obtained when used with Hydrogen-Boost.
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