firefly1_0 New Reader
2/22/16 1:39 p.m.

hey all,

did the maths after i had my injectors flow tested and got totally confused by the results...

i was told that the injectors were 330cc when i bought them and then when tested they read 79.2cc/min so i went and created this. i had posted this on other forums a long time ago but always forgot to post it here.

Questions that you need to ask the testing facility when you get testing like this done.

-final flow rate per minute = 79.2cc/minute

-pulse width used during test = 6ms

-test RPM = 2400

First we need to figure out how long the injector would need to be open to flow the tested volume if it were fully open.

In this example its time would be 14.4 seconds if we assume that the injector opens once every cycle."

    Duration = RPM X Pulse width in milliseconds / 1000                     
eg. 14.40 = (2400 X 6 ms) / 1000

This calculates the "Minute factor" to allow the final calculation to be done for one minute of flow.

    Minute Factor = Duration / 60 seconds

eg. 4.17 = 14.4 / 60

We know that 79.2 cc of fuel will flow in 14.4 seconds so we use the "minute Factor" to calculate what the flow will be for one minute.

    Full Open (advertised) Flow = as tested Flow CC x Minute Factor

eg. 330.0 = 79.2 x 4.17

To Convert this to Lb/Hour of fuel flow at 15°C we multiply 330.0 by 0.09523809 and we end up with 31.43 Lb/hour

nancy2809 New Reader
2/23/16 3:39 a.m.

hello everyone In reply to firefly1_0:

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