Warning HHO is very explosive.
The chemicals used can cause severe burns and blindness.
For me I got 10 to 15% better gas millage from 30 MPG to 35MPG on
a 97 Saab, Problem was it
Slowly deteriorated with time giving less and less HHO gas.
This is ( to me ) a major problem.
MAY 2013 UPDATE
Since this was posted I have been working with water vapor injection.
Presently I am using a ultrasonic humidifier powered by a 400 watt
12 volt to 110 vac converter to
generate water vapor and injecting it behind the air filter on my 97 saab.
It really seems to work with my mileage going from
30 mpg to 35 mpg. Perhaps I am missing something but this is
the approach I would suggest.
Also installing a humidifier is a lot easier than the plates and solutions
needed for HHO.
In my case the generator is in the trunk and a 1 inch PVC pipe runs under
the car to the engine compartment.
This page includes two new techniques. One is
the use of a spiral plates to achieve a large plate area in a small
Another technique we use is to use a DC current limiter to
provide a constant current that does not change with cell temperature.
It uses 4 headlight bulbs with the 8 filiments wired in paralled
to produce a non linear resistor.
About 57 Amps
are usually required
to produce 1 LPM. his is beyond the drain we wish to place on a
car's alternator but fortunatly 14 volts are far in excess of the voltage
required to produce hho. Thus it is possible to make 4 small
units each producing about 1/4 of the total and connect them
in series. This reduces the current drain to 57 /4 or 14
amps per lieter of gas .
This unit is composed of 4 cells made from 3 inch
PVC pipe each 9 inches long. A pipe cap is glued on the bottom
and a rubber seal is used on the top. The rubber seal is clamped
in place to make a gas tight seal but still allow it to come off in
the event of an explosion.
I used a 6 inch by 100 inch roll of 316 stainless
steel shim stock .007 thick. It was purchased from Macmaster
Carr. This roll was cut to eight pieces each 12.5 inches by
6 inches. The pieces were stacked on a plywood form and holes
to clear a number 8 screw were drilled to hold the spiral in place.
The dimensions required for the holes are all measured from one
end. The dimensions ( in inches) are 0, 0.5, 1.77,
3.24, 4.917, 6.783, 8.884, 11.102.
The holes are about 3/8 inch from the top and bottom of the plates.
This is shown below.
The two spirals needed were made by curling each of the
stainless pieces on a length of 1 inch copper tubing. Then
they were held together with 1/16 inch wire welding rod. A
drill was used to insure that the holes were all in allignment. Then
8-32 flat head nylon plastic screws and nuts together with 1/4-20 nylon
nuts used as spacers were used to assemble the 2 spirals that lie
inside each other. Two pieces of 1 inch by 2 inch stainless are
used to connect to the copper electrical connectors.
This is all shown below.
A 1/4 inch pipe tap was used to tap a hole for a 1/4
inch pipe fitting that connects to 1/4 inch PVC tubing.
ELECTRICAL CURRENT FEED-THRU.
To make the current feed-thru gas tight 2 1/4 -
20 flat head brass screws were soldered together.
Then 2 holes were drilled and countersunk. The taper of
the flathead screws made a gas tight seal.
It was found necessary to protect the gas outlet from the water
KOH mixture. I used a length of 1/2 inch PVC
pipe that was cut to 3.075 inches long. The ends were rounded
with a file and holes drilled into the top and bottom. They are
Then the gas outlet is unscrewed and a C clamp is used to distort
the 3 inch tube to insert the tubes as shown here.
A current regulator was made from 8 headlight bulbs. These
had all 16 filiments connected in parallel. They are shown here,
The completed box with the transparent cover looks like this the
meter reads milivolts which is equal to the current in amps.
Now for installing. I used 2 lenghts of 3 conductor wire with
all 3 wires in parallel and 110 colt connectors as they were cheap.
Here are the 2 wires on the battery. the postive one goes through
a 40 amp circuit breaker. One wire goes to the screw. The second
is soldered to a nickle. The nickle is then cut flat with
a hack saw and inserted in the connector blades of the circuit breaker.
The 2 wires go to the trunk,
Where they go through the box to the four cells:
The crate prevents tipping over. A copper tube then runs back
to the air cleaner:
PS vehicle is a 97 Saab 900.