DIY Injector Flow Bench

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ironmanisanemic
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DIY Injector Flow Bench

Post by ironmanisanemic » Tue Oct 10, 2017 2:19 am

Hello,

For the last few years i have been frustrated with most injector companies only giving static flow instead of full injector calibration data. Now i do know that for most, its workable. But if your like me, it is going to drive you up the wall when your trying to dial in the MAF and your injectors. Sometimes it felt like i was pissing into the wind trying to get things right. Looking for more information i found that Injector Dynamics outlines a pretty easy to follow article on Fords injector characterization. http://injectordynamics.com/articles/fo ... erization/ But alas, they dont appear to offer characterization services to the general public. Another good article i came across was from Greg Banish, https://calibratedsuccess.com/live-cour ... erization/ but again no dice in giving any indication on where it could be done. Finally i found a place that outright will do it, http://www.deatschwerks.com/support/ser ... r-services. But they are on the pricey side, costing $90 for the battery offset test, and another $90 for the "linearity" test. That was more than i spent on the injectors NEW! So i set off to design a low cost, user friendly, use what you got type of injector flow bench. Now, i know this is no easy task, but so far i have the bulk of the code written that will run on any Arduino uno or mini. It leverages the 16bit timer to control the frequency and the duty cycle, and uses an 8 bit timer to control how long to run the test. For now it uses a piece of software called MegunoLink Pro for the control interface. https://www.megunolink.com/ Unfortunetly, its not a free piece of software, but there is a trial version that i believe will work for just checking out what ive done. I plan on getting the ASE tech doc that discusses injector characterization in more detail, but i do know that most all testing is done at a simulated 6000RPM, and a pulse width from 0-10ms. This correlates to 0-100% duty cycle since 6000RPM equates to only a 100hz square wave. I plan to further expand upon the code to get away from the MegunoLink software, and move to a LCD screen with some form of menu and user interface, as well as add feedback for pump and fuel pressure control. Ive also started to rough out the hardware side of things and have made up a small PCB that currently only is controlling 1 injector, but can easily be scaled up, once the final circuit has been designed. I havent begun to draw up the enclosure, but in the grand scheme of things thats the easy part. I will attach a few pictures, screen shots as well as the source and dashboard for megunolink so others can give it a try. Im very open to suggestions, help with coding and circuitry as i am still very green in both aspects. If this becomes popular enough i could put this up on gethub, but for now posting it here will suffice.

EDIT

I forgot to add that i know there are a ton of DIY "Injector benches" on the internet. What i aim to do with this, is have a repeatable platform that can perform characterization of unknown injectors or decapped injectors. It can also serve as a cleaning station. What other solutions have failed to address is the repeatability factor. Most ive seen trolling youtube use a toggle switch and a stop watch to flow injectors.

I will try to make up a small video of my setup working and hopefully post it up tomorrow.
Attachments
IMG_20171008_180841.jpg
photo of the proto control board
IMG_20171008_180841.jpg (171.51 KiB) Viewed 124 times
variable freq and DC.zip
source file as well as the control interface file for megunolink
(5.6 KiB) Downloaded 4 times
megunolink screenshot.jpg
screenshot of the control interface
megunolink screenshot.jpg (65.35 KiB) Viewed 124 times
1989 Ford Bronco:
-393W, Edelbrock Performer RPM heads, ProComp Upper and lower intake, Custom Comp Hyd Roller cam, 10:1 compression, 30lb injectors, 75mm TB, Pro-M 80mm MAF, equal length short tube headers, 2.5 inch y pipe merged into single 3 inch with hooker aerochamber muffler and no cat, QH w/ BE and EA running U4P0, AOD

1995 Ford Mustang GT
-Bone stock minus the QH. 5 Speed. T4M0

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cgrey8
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Re: DIY Injector Flow Bench

Post by cgrey8 » Tue Oct 10, 2017 7:23 am

That's excellent work.

I do know Fuel Injector Connection has standard flow bench machines that can pulse the injectors at different PWs. The machine doesn't "simulate" RPMs. It's more interested in the length of the ON PW and the total time the test runs. I think most of the tests they run and value the results of are with a 50% duty cycle. However I believe the machine can do anything from 10-100%. The setup they show on youtube is the same setup I saw when I went to their facility (a shop in the back of the owner's home).

I still have, floating in the back of my head, hope of partnering up with someone to design an open source EEC replacement similar to what MegaSquirt uses, but based on modern stuff like Linux and Java. While there are real-time aspects that simply cannot be done in this environment, there are hardware solutions out there now that have ARM Cortex A-series and M-series processors on the same die that would work perfectly for this kind of project. The real time stuff could go in the Cortex M processor (running at ~200MHz) while the Cortex A could run Linux and a JVM at 1GHz including giving the hardware the ability to do WiFi (not Bluetooth), possibly run a web-based interface, and massively more programming flexibility & debugging ability than reverse-engineering 20-30 year old BINs.
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

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ironmanisanemic
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Joined: Tue May 24, 2011 8:33 pm
Location: Vandenberg AFB, CA

Re: DIY Injector Flow Bench

Post by ironmanisanemic » Tue Oct 10, 2017 8:23 am

I say simulate RPM only because it's easier to understand by most to say RPM than some arbitrary frequency. I'll show it in more detail in a video, but the frequency and pulse width are all calculated and displayed on the control interface so you still have all of your information. Right now I can select any value from 1 RPM up to say 20000rpm (haven't actually calculated out the upper limit, ive tested it to 18000rpm) 0.01% dc - 100% dc, and 0.01 Second on time to 70ish days(it's the theoretical max value in the timer that's being used for the time on). I would like to add the ability to sweep the RPM and simulate dynamic driving like what the commercial units do. But right now I need to focus on getting a reliably working schematic for the electronics, and get a few boards made up to test.
1989 Ford Bronco:
-393W, Edelbrock Performer RPM heads, ProComp Upper and lower intake, Custom Comp Hyd Roller cam, 10:1 compression, 30lb injectors, 75mm TB, Pro-M 80mm MAF, equal length short tube headers, 2.5 inch y pipe merged into single 3 inch with hooker aerochamber muffler and no cat, QH w/ BE and EA running U4P0, AOD

1995 Ford Mustang GT
-Bone stock minus the QH. 5 Speed. T4M0

ironmanisanemic
Regular
Posts: 159
Joined: Tue May 24, 2011 8:33 pm
Location: Vandenberg AFB, CA

Re: DIY Injector Flow Bench

Post by ironmanisanemic » Wed Oct 11, 2017 8:17 am

So last night I was able to record a shortish video on how things work. Hopefully it's easy to follow. https://youtu.be/lcwjgRoaD-Q
1989 Ford Bronco:
-393W, Edelbrock Performer RPM heads, ProComp Upper and lower intake, Custom Comp Hyd Roller cam, 10:1 compression, 30lb injectors, 75mm TB, Pro-M 80mm MAF, equal length short tube headers, 2.5 inch y pipe merged into single 3 inch with hooker aerochamber muffler and no cat, QH w/ BE and EA running U4P0, AOD

1995 Ford Mustang GT
-Bone stock minus the QH. 5 Speed. T4M0

m0l0
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Joined: Thu Jan 05, 2006 8:35 pm

Re: DIY Injector Flow Bench

Post by m0l0 » Thu Oct 12, 2017 12:19 am

Excellent project , the testing seems for be excellent for a diy project even at this stage, i am glad you are sharing the source code , do you mind sharing a little bit of the raw schematics and p/n for the mosfet?? maybe i can help with a little parallel tests
89 LX : 351w AFR185,Trickflow R Intake,Lunati 51014,BBK Headers A9L2
97 Cobra : Stock Just Tweecer RT

ironmanisanemic
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Posts: 159
Joined: Tue May 24, 2011 8:33 pm
Location: Vandenberg AFB, CA

Re: DIY Injector Flow Bench

Post by ironmanisanemic » Sat Oct 14, 2017 2:54 am

here is the part number for the FET PSMN022-30PL i just had a bunch of these laying around. They are far from ideal with a relatively high RDS on resistance, but are still a good MOSFET for the price per unit. I attached a basic schematic of how i have it wired currently.

The pull down resistor is a 15k
the 2 diodes arent completely necessary, but are there for reverse voltage protection. They can be any diode as long as the one on the ground side of the MOSFET can handle higher currents.

The rest should be fairly straight forward.
Attachments
Untitled Sketch_bb.jpg
Untitled Sketch_bb.jpg (97.9 KiB) Viewed 60 times
1989 Ford Bronco:
-393W, Edelbrock Performer RPM heads, ProComp Upper and lower intake, Custom Comp Hyd Roller cam, 10:1 compression, 30lb injectors, 75mm TB, Pro-M 80mm MAF, equal length short tube headers, 2.5 inch y pipe merged into single 3 inch with hooker aerochamber muffler and no cat, QH w/ BE and EA running U4P0, AOD

1995 Ford Mustang GT
-Bone stock minus the QH. 5 Speed. T4M0

m0l0
Gear Head
Posts: 52
Joined: Thu Jan 05, 2006 8:35 pm

Re: DIY Injector Flow Bench

Post by m0l0 » Sun Oct 15, 2017 8:16 pm

Excellent will start to build it this week, i will post as soon is built
89 LX : 351w AFR185,Trickflow R Intake,Lunati 51014,BBK Headers A9L2
97 Cobra : Stock Just Tweecer RT

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