Time for a New Look at Fuel Injector Testing and Characterization

[eficalibrator]

Let me preface this with a few points. I do not sell fuel injectors, nor do I really care where you bought yours. This report is just the result of a bunch of engineering tests that I recently ran. You can duplicate all of this yourself if you're familiar with SAE J1832 and have a test bench with controls capable of delivering the proper test conditions. The report is just meant to raise the bar for awareness in the performance industry. And finally, no I will not give you my characterization data from any of the injectors tested in this report unless you want to hire me as an engineering consultant. If you're mad because you don't like it, please remember this is just data, math, and science. I just report what I see.

Calibrated Success Fuel Injector Article #2

[DSteck]

Where's the like button?

Great job!

[Chris@HPTuners]

Outstanding!

[zl1killer]

Opening time is not the only thing in play here,
remember? It appears that the closing delay and tip filling phenomena are now driving the behavior more
prominently. The result is that the offsets are very different and so are the corrections necessary for short
pulses. In GM-tuning-speak, this would be the short pulse adder table values

this is what I wanted to know, and particular people would not simply sate this. THANK YOU!!

Also, what I gather from this is for the most part it is better to start with the higher flowing injector from the manufacturer and not have injectors drilled/modified unless they come with the updated data after the modification.

[zl1killer]

explain fuel mass versus cc per pulse.


I took the exact tune & data I had for the ID725s on my car and installed the FIC725s (more like 732) and ran the car just like that, no tuning changes and my fuel trims were trying to pull fuel as I had a larger injector installed. So then I corrected the IFR and drove the car around and noticed no difference in AFR or fuel trims from having the ID725s installed.

so then I loaded the FIC data in and noticed no difference.

Rewind to a LONG time ago, like 3 years or slightly more, I went from the stock pintle (i think) 28.8LB/hr from 2001, to a 42# Lucas/Delphi disc injector from racetronix, and I updated the IFR table and from what I can remember didn't touch the other tables, if I did, they were likely lowered. The car ran fine, commanded AFR was there, fuel trims were good and the car behaved great. Now, at the time did I know about all this data with injectors?...no, nor did I understand it all, and I'm still learning things now. So at the end of that, did I maybe tweak the tune around the un-tuned injector tables.....maybe.... did I notice...no. So I guess maybe I hacked the tune as people like to say? Different ways to skin the cat? Did I ever notice the car running funny ... no.

[Redline MS]

Greg......thanks for the sneak peak... Very well written... The moral is that there is a reason why GM utilizes these characteristics and they actually work. Those who spend time to get the work done will have a superior product.

The same way I have been done dealing with $300 wide bands for calibrating I'm not going backwards with injector data.... If you can provide the correct data I'm not interested.....

Launch sequence activated...... Lol.

HT

[DSteck]

Launch sequence activated...... Lol.

Kind of makes me want to wire up this three axis accelerometer and measure NVH differences to put a number to the smoothness!

[imphat0260]

Awesome read Greg

[1998Ws6]

well written data as always Greg,

HT, I agree on the $300 wide bands comment as well. I just picked up 3 AFM1000's, so I will never have to question the accuracy of my equipment either.

Ryan

[Redline MS]

well written data as always Greg,

HT, I agree on the $300 wide bands comment as well. I just picked up 3 AFM1000's, so I will never have to question the accuracy of my equipment either.

Ryan

Good choice. I have so many LM1's, LM2's, LC1 and every other brand its disgusting. Finally bought two AFM1500's with serial output and they are flawless. Done dealing with ground offsets and crappy sensors...

Any hoe.....its the same issues with injectors....I've done my time as a calibrator guessing and wondering if the "constant" data from injectors is correct and its effects...now I've experienced it.

Back in 2006 we had twin turbo charged my Z. Using "60s" and the best guess at data I could find. Car had decent drivability, startup was ok and what did I know......then we obtained the correct data and with nothing else but the correct data being changed the car was like stock! Now this was a built 432 motor as it was but all aspects of where you spend the most time calibrating was fixed in one quick swoop. That was it for me....

At the end of the computers thought process its trying to combine accurate fuel mass to accurate air mass....period....dial in VE and MAF....tell the PCM exactly what to expect at a given pulse width and you go from a "tuner" (which is what I do with my guitar!) to a calibrator.

While I'm on a rant......maybe they can make a section here for the guys that just bought HPT, have one post and start begging someone to send them a TUNE! Roll up your sleeves and figure it out or bring it somewhere.....

I'm glad I got that out.....

HT

[zl1killer]

The same way I have been done dealing with $300 wide bands for calibrating
HT

holy footballs batman, $1500 for an AFM1000 & $1700 for the AFM1500 (via price quotation)

[Redline MS]

holy footballs batman, $1500 for an AFM1000 & $1700 for the AFM1500 (via price quotation)

Yep and just bought another one for out of shop adventures... It solved the head games with wondering if the readings where correct all the time.

Plus the serial output works much better then analog and I can daisy chain up to 6 units together through one serial line.

My point of brining up the WB was paralleled with the same mind game with data and always wondering if the fuel mass I'm needing is what I'm commanding and getting....

Anyone who calibrates for a living should have no problem factoring this thought process as it eliminates a lot of call backs and makes for happy customers!

Howard

[eficalibrator]

holy footballs batman, $1500 for an AFM1000 & $1700 for the AFM1500 (via price quotation)

ECM actually gives a really decent discount to the guys who take my live classes. They like having educated customers who understand the value of good equipment and test methods.

Like Howard, I have several ECM units. I currently own a LambdaPRO and an AFM1500. My time is worth a lot and I don't like wasting it on crappy equipment or second guessing whether I can believe an air-fuel reading or not. I never chase ground offsets on my tuning rig and the data is dead nuts repeatable. I've had students who have literally wasted thousands on bad sensors in addition to their own lost time due to "bargain" widebands. It's a false economy to buy a cheap wideband if you plan to use it regularly like a pro shop should. A good wideband should make money in the long run.

[DSteck]

I need to get off my ass and order my AFM-1000. I trust my NGK AFXs, but it's time for professional grade.

[1998Ws6]

If buying new, I'd go with the 1500 not the 1000 just to have the serial option in the future, but I found my 1000's used for a great deal.

Ryan

[zippy performance]

At work I use a Horiba wideband. I have two hooked into the dyno so when I want to I can check both sides. Anyone else out there use a Horiba?

That is a good article. I have pretty much cut out customers bringing me in vehicles with drilled injectors and in general any injector I have no data on including the pain in the ass FAST brand of injectors. It's pretty hard to be the consistency and nice spray pattern from the Siemens Deka injectors. I have a very nice ASNU injector machine at work which I have used to run tests on various injectors and completely find the same type of results that you see. Not only is the fuel quantity not linear, but the spray pattern on them is horrific and inconsistent.

[Redline MS]

I need to get off my ass and order my AFM-1000. I trust my NGK AFXs, but it's time for professional grade.

I bought the add on digital gauge with both of mine as well. In our dyno room we have one mounted on the wall for a "quick" reference. My portable one we made a windshield suction cup mount using a navigation mount from Best Buy.

I'm on the same sensor for well over a year and we use race gas often. Couldn't be happier.

Howard

[LSxpwrdZ]

I have also been using just the NGK AFX along with a couple Haltech widebands. Where do you guy's buy your ECM widebands at? I've wanted to get one for a while just no time to look for them as busy as we've been.

[eficalibrator]

ECM will sell to you directly if you call and talk to Ron or Fabio. They also give a decent discount to the guys who have been to my live classes since they like selling to educated consumers. They will still sell to you even if you haven't been to my class, but I can't quote prices since I'm not their pimp.

www.ecm-co.com

[DSteck]

What if I just tell them Greg Banish is a swell fella? Think they'll discount me then? Haha.