pcmhacking.net

Hey All,

A little project I've been meaning to put together for AGES, just to test spray patterns for leaks & flow rate! especially after Jayme has mentioned some injector's stream & don't go out onto back of valves i thought I'd better make sure I use good injectors!

See if everyone can figure where the main parts are from(3 different models & 2 different manufacturers!)

the fuel rails look like a vt v6 cut in half.

not sure what other parts, but the fuel pump looks like some sort of vn/vs type of in tank pump.

Are you using an ECU to pulse the injectors?
I was thinking of making something similar, with a pic controlling the injector duty cycle and test time to be able to accurately determine cc/min @ various pressures.
Are your test tubes graduated?

LOL, yeah rail is vt v6 cut in half, No the fuel pump is Found On Rubbish Dump styled & an over kill really(I have a vt that I'll prolly use)!

Festy No I thought about using the 808 with the jim stim but haven't got it set-up properly so for now I'll just used timed straight 12v or I can do the 5 pin relay trip wire to pulse trick! For now it's purely looing at patterns & timing & measure volume for exact same time & pressure!

I didn't think DC was good for injectors? Or does that only apply to low impedance injectors?
A 555 timer and a mosfet would give you reasonable control of the duty cycle.

Well thats news to me, with my testing so far I have just used 12v car battery lying around!

But I might have to put those items on my wish list with you festy with the nvram replacement your putting together LOL!

I found a pic of an ASNU cleaner/flow test bench screen showing the parameters for a flow measurement: That shows 50% duty cycle, and I assume a 36ms period.

Here's an interesting slow motion video of some dodgy spray patterns shown on one of these rigs - http://www.youtube.com/watch?v=NIz5c9MLCls

You could almost get away with a 12v transformer and a diode to give a reasonable pulse, but the sine wave would probably mean the injectors would open a bit slower than they should.

You can make one on a 555 timer circuit, i did one a while ago, this was just for a single injector but could be adapted for larger scale if need be, using different mosfet and caps/resistors for timing, i will see if i can find where i got the schematic from

this was it.

http://www.dinofab.com/fuel_injector_tester.html

good info here!! i have often thought about making an injector tester so i might have to start looking at it now!!

and i love the video, thats a perfect illustration of why drilling injectors is not a good idea!