Note: These instructions are also on the accompanying CD in PDF
format so you can copy it to your computer.
The open flow test kit helps simulate what the nitrous fuel system is
doing without running the engine or turning on the solenoids. What it
cannot do is simulate g forces, heat , engine vacuum, line parasitic
Hookup: disconnect the outlet hose from your fuel regulator and
connect the OFT to the regualtor. Put the hose with the jet in a bucket
or the fuel tank. The on/off valve will simulate open and closed readings.
Closed readings are interesting only in that it tells how much strain is
being put on the pump. Open, flowing pressure is what counts.
Observe all safety precautions.
Single plate/1 jet
Install a jet the same size as is used in the plate. The on/off valve will
simulate the open and closed solenoid.
Adjust your pressure as desired with the valve open.
Multiple jets / foggers / plate: Figuring your test jet size
Formula: Diam. X Diam X .7854 x N = flow test jet area
(N is the number of fuel jets)
1. Take the inside diameter of one jet
2. Multiply times itself
3. Multiply times .7854
4. Multiply times the number of fuel jets used = area of test jet
Example: .032 x.032 x .7854 x 8 = .0064336
Convert the total area to a jet diameter.
Formula: AREA / .7854 x SqRt
1. Area of test jet divided by .7854=
2. Hit the sqrt key on your calculator = Diam. of test jet.
Example: .0064336 divided by .7854 =.0081914, hit sqrt key, result
=.0905063 or .090 (or .091 jet if you round off.)
Look at the companion cheat sheet. Choose your jet diameter. Multiply
the listed area x number of jets. Locate an area that closest matches
you result. That will be your open flow test jet
If you have 2 or more stages running off the same fuel control. Figure
the area for each stage, then add together to get total area with all
Use the included free software for figuring the open flow test jet.
Open my computer/your cd drive/
Double click the openflowsizer.exe to install
Check out the Nitrous Master software where all this is figured for you.
Open Flow Test Kit Intsructions
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.
Urbana IL, USA
217 531 1770
M-F 9 - 5 CST
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