Pinfield357

i just got my injectors back from injector.com and on their data sheet is says that after the cleaning they are running at 180 cc/min at 43 PSI? is that right or dont they puch them to the max when they test them?

caue i thought that they where suposed to be flowing 550 if thats the case then there is something very very wrong here.

RETed

You're right - "180" is wrong.
At that test pressure level, it should be showing above 600.


-Ted

Evil Aviator

By my calculations they should each flow about 594cc/min @ 3 Bar. Regardless, 180cc/min is totally wrong.

You may want to ask them that. Most flow testing is performed with a simple system which runs the injector at 100% duty cycle for 15 sec at 3 Bar (43.5psi), the output is measured in a beaker, and then the output is multiplied by 4 to yield the output per minute. However, more advanced testing equipment will actually run the injector at certain pulsewidths.

Pinfield357

ok this is straight off the Marren Fuel Injection info sheet:

make/model RX-7 T/2
Injector Type: P&H 2.4 ohm
Injector Part NO: 195500-1370
Injector Make: Nip-Denso
# of Injectors 4.0
Test Pressure: 43PSI
Test Pulse: 6.0 MS
Gravity Weight: 0.75

Before cleaning in C.C. of Fuel Per/Min

1) 169.1------spray pattern: no good

2) 180.0------good

3) 178.2------good

4) 172.7------no good

"Reverse cycle" (i dont know that this entails)

all are dirty

After Cleaning

1) 180.0-------good

2) 181.8-------good

3) 178.2-------good

4) 179.8-------good



Im so confused it looks like they where trying to get them to 180cc but not even the NAs run those

NZConvertible

You'll only get 550cc/min if you hold the injector open during the test, i.e. 100% duty cycle. Injectors are normally tested by being pulsed like they would be in the engine. You can see in the test results that a pulsewidth of 6.0ms was used, but there's no pulse frequency so you can't work out what the actual duty cycle was. 30% is pretty typical so if you divide the results by 0.3 you get ~600cc/min. The test pressure used is much higher that the Mazda spec pressure (250kPa, 36psi) which is why is why the results are 50cc/min higher than spec.
Don't worry, your injectors are perfect.

BTW, reverse cycle is just another term for backflush.

Pinfield357

cool thanks for the help guys