By David Koehler
copyright 11-30-05
Images by Dave Koehler, Koehler Injection and Combo-Flo
All Text and images on this website are copyrighted by David Koehler 2000 and beyond
All sales are final. Items and services provided by Koehler Injection are intended for off road use only.
No responsibility whatsoever will be accepted by Koehler Injection for any damage, injury or loss resulting from their use.
Nitrous Master.
Postal Money Order
A Review of Combo-Flo Air Operated Solenoids
Combo-Flo 500 plate air operted solenoid
You may create a link to this article.

You may not
copy / paste it to another site without permission.
You may create a link to this article.

You may not
copy / paste it to another site without permission.
Combo-flo V8 fogger
machine shop engine industrial balancing, fuel injection  flow tesing urbana IL
Urbana IL, USA 
217 531 1770  
M-F  9 - 5 CST
Click to call
Many Photos may be
enlarged by clicking on them.
Postal Money Order
Nitrous Oxide
Cart Total
In the future, all racecar electrical-activated items will be wireless.
You heard it here first.

Why would I wish for such a thing? I always found the proper wiring
of a race car to be the most time consuming and sometimes annoying
of all race car systems. I want a better way.

In the meantime as I trudged on, dealing with wire, numerous relays,
switches and the labor required to install and maintain a nitrous
system I dreamed of an air system to control the nitrous. An air
operated system could virtually eliminate any if not all of the amp
draw, all the wires, terminal blocks and relays.

A broad statement can be made that 95 percent of racecar problems
can be traced to electrical issues so if I could eliminate some of the
electrical hardware the percentage of potential mystery problems
would decrease. A single stage plate can pull down 10 - 40 amps and
a nozzle system can pull down anywhere from 20 to 50 amps per
stage depending on the solenoids used. This is a huge amount of
battery drain. If I could get rid of that amp draw perhaps but not
likely, I could quit badgering nitrous racers to install alternators and
voltage controllers.

At the very least, a huge portion of the battery capacity could be
better utilized keeping the ignition doing the job it was intended to
do. With less amp draw and likely lighter weight units it would almost
be like free HP. I believed air could be the next step until the no loss
battery and miracle wireless; no amp solenoid coils were invented. I
really wanted to simplify my job but alas, my education was
insufficient in this area so nothing tangible ever came of it.

Air operated systems have been around forever in the industrial
world. If you work in any kind of manufacturing I will bet that there is
some item or function that is air controlled. Air throttle controllers,
shifters and trans brakes have been around in drag cars for a while
and proven their dependability and quick action. The nitro Fuel teams
utilize pretty complicated air logic systems to run their fuel and clutch
and I just figured an air operated system had to happen some day.

Eureka! Doug Mills of Mills Specialty Products has come to the
rescue. His company, Combo-Flo is producing air operated valves for
nitrous systems. They are designed to replace and upgrade nitrous
systems that currently use electric solenoids.

After working with them for a while I felt that calling them pneumatic
operated nitrous valves was a bit long, boring and did not make for a
neat acronym sooo. I hereby dub them Airnoids.