12 Hole Injector Upgrade - Finally Tested (2 Viewers)

[dirtydeeds]

the concept is the same One Large pizza cut in 4 or the same One Large pizza cut in 12

Good feedback, thanks!

Do you happen to have MPG logs? I've got a large set for my own 100's, but would love to start compiling others and see if we can find some consistent improvements. IE Premium/Regular, 12/4 hole, tire size, bumpers, etc...


**Edit I should add: The difference felt in situations like yours is possibly the result of old, slightly dirty injectors and new, clean injectors. Could be 12 vs 4, but without back to back testing of a cleaned 4 hole, hard to tell what the main contributor was.

The main contributor was the fact that 12 hole injectors atomizes the fuel better which causes more of it to vaporize, after all its the vapor which burns not the liquid fuel With more of the fuel being burnt and not being put out into the atmosphere as unburnt hydrocarbons the engine runs more efficiently. That’s the main point of running 12 hole injectors.

This is not an unusual experience

 

[suprarx7nut]

The main contributor was the fact that 12 hole injectors atomizes the fuel better which causes more of it to vaporize, after all its the vapor which burns not the liquid fuel With more of the fuel being burnt and not being put out into the atmosphere as unburnt hydrocarbons the engine runs more efficiently. That’s the main point of running 12 hole injectors.

Possible Counterpoint at the heart of our discussion: That’s the main point of running 12 hole clean injectors.

We have to be careful to separate the two variables - cleanliness and hole design.

We all know and agree cleanliness matters, especially after 200k miles. The question then becomes: With equally clean injectors, is there a quantifiable difference between OEM 4 hole and retrofitted 12 hole?

Our data so far has been unable to show a difference. In statistical speak, we cannot reject the null hypothesis that the two are equal. Anecdotal evidence is mixed with very few, perhaps only one person in this discussion (@dirtydeeds ) having tested clean 4 hole back to back with clean 12 hole. Since @dirtydeeds sells the product in question, data becomes even more important to mitigate the risk of bias.

Since we know cleanliness matters, I think we all need to be aware dirty 4 hole vs clean 12 hole conflates the issue at hand.

 

[skhochay]

The main contributor was the fact that 12 hole injectors atomizes the fuel better which causes more of it to vaporize, after all its the vapor which burns not the liquid fuel With more of the fuel being burnt and not being put out into the atmosphere as unburnt hydrocarbons the engine runs more efficiently. That’s the main point of running 12 hole injectors.

This is not an unusual experience

whot? did you come up with that yourself did you know yourself what you just said?

 

[dirtydeeds]

Possible Counterpoint at the heart of our discussion: That’s the main point of running 12 hole clean injectors.

We have to be careful to separate the two variables - cleanliness and hole design.

We all know and agree cleanliness matters, especially after 200k miles. The question then becomes: With equally clean injectors, is there a quantifiable difference between OEM 4 hole and retrofitted 12 hole?

Our data so far has been unable to show a difference. In statistical speak, we cannot reject the null hypothesis that the two are equal. Anecdotal evidence is mixed with very few, perhaps only one person in this discussion (@dirtydeeds ) having tested clean 4 hole back to back with clean 12 hole. Since @dirtydeeds sells the product in question, data becomes even more important to mitigate the risk of bias.

Since we know cleanliness matters, I think we all need to be aware dirty 4 hole vs clean 12 hole conflates the issue at hand.

Clean 4 hole compared to clean 12 hole would indicate the winner is the clean 12 hole all day since they atomize the fuel way better than clean 4 hole injectors do, simple science dictates that, regardless of whom sells them.

My bias is based on what makes the truck drive better according to many enthusiasts and experts in the field. My definition of an expert would be Toyota engineers or others whom actually tune vehicles, not an engineer from some other field whom refuses to take advice from an actual expert in this field then makes assumptions based on a single test performed while not actually driving the test vehicle.

 

[GTV]

So @dirtydeeds, if you were looking for data to back up the butt dyno in what ways would you test it? Assuming you had the time and equipment to do so.

 

[nukegoat]

So @dirtydeeds, if you were looking for data to back up the butt dyno in what ways would you test it? Assuming you had the time and equipment to do so.

Someone already asked that. He did not provide this info

 

[jLB]

Clean 4 hole compared to clean 12 hole would indicate the winner is the clean 12 hole all day since they atomize the fuel way better than clean 4 hole injectors do, simple science dictates that, regardless of whom sells them.

My bias is based on what makes the truck drive better according to many enthusiasts and experts in the field. My definition of an expert would be Toyota engineers or others whom actually tune vehicles, not an engineer from some other field whom refuses to take advice from an actual expert in this field then makes assumptions based on a single test performed while not actually driving the test vehicle.

(Admittedly)

According to Denso:

CIII (4-hole) injector droplet size is ~90um​

CIII (12-hole) injector droplet size is ~60um​

UC (4/12-hole) injector droplet size is down to ~50um​

What is the optimum spray pattern and droplet size, for an otherwise stock 2UZ-FE?

What objective measurements were used to determine this optimum, and what expert did them?

Is this "simple science" more theoretical than practical?

Am I going to see a ~33% reduction in fuel consumption, with a ~33% reduction in droplet size?

Should we just bypass 12-hole injectors, and convert to LPG or CNG, to even further reduce (or eliminate) the droplet size issue?

Which injector do Toyota/Denso engineers recommend for the 2UZ-FE?

Was this recommendation based purely on droplet size, or were there other parameters that were considered?

What are the actual credentials of the "others who tune vehicles" experts?

 

[SlowBuild]

Someone already asked that. He did not provide this info

He’s an expert, he said so himself. He doesn’t need data, he already knows the answer. Data is secondary and a waste of time.

 

[red66toy]

Kudos to @suprarx7nut and crew for taking the time and money to add some useful and REAL data to the mud community. I love this forum for the great members who truly want to give back and help others.

 

[Eyedaho]

Someone already asked that. He did not provide this info

That's what I was getting at with the mpg question. If the difference only shows up in real world driving as stated, and less throttle input is needed, it should be pretty easy to collect some valid fuel economy data in the real world.

 

[nukegoat]

That's what I was getting at with the mpg question. If the difference only shows up in real world driving as stated, and less throttle input is needed, it should be pretty easy to collect some valid fuel economy data in the real world.

Yeah or any number of other data series... throttle input to torque ratio etc

 

[suprarx7nut]

I just stumbled across something that I didn't look too much at before. I was helping a friend change their 2UZ exhaust header (GX470 with integrated cat) and noticed the different part numbers for the upstream/downstream sensors. Hmm, is one a narrowband and the other wideband? The tests in Techstream seemed to only make sense if upstream was wideband.

Sure enough, it's listed as wideband from Denso and the Lexus manuals take care to differentiate between the narrowband downstream O2 sensor and the AFS (upstream air fuel sensor). Denso's site is annoying simple so I went to look it up on common part store listings and sure enough, the sensor type is wideband. The factoring wiring manual shows different wiring schemes for the two sensors - upstream air fuel sensor and downstream O2 sensor.

Since the AFR sensor measurements have been touched on a few times on this topic, I figured it was worth sharing. Not sure if it changes anything, but I thought it was neat that the OEM ECU seems to use a wideband for fuel control.

Summit listing:

NTK listing on Autozone

 

[jerryb]

When they went v intake is when I think they swapped, or if you don't believe that then assume 05/2005 production.
Even writing that reminds me I still want straight pipes and a muffler.

Thanks for the Dyno work and info!

 

[C6H12O6]

Late to the party, but since this was opened back up, I'll add a little (probably meaningless) fuel to the fire. Pun definitely intended.

I get the claim that the 12-hole injectors atomize better and that leads to less fuel used for the same power. The newer 5.7L engine's use of the 12-hole injectors probably has as more to do with that efficiency and the resultant cleaner emissions than anything. That sounds great, but that really should show up somewhere in the data, and it seems not to so far. Is that because of a flaw in the testing somewhere? An uncontrolled variable throwing a wrench in the works? Maybe. Or, it could be that the wide-band upper O2 sensor does a better job than previously suggested at monitoring and controlling AFR, to the point that the difference is negligible on this motor.

Here is where I get hung up. That measureable difference between clean 4-hole and clean 12-hole injectors (if any) would probably be seen in the fuel consumption, which is almost impossible to measure accurately. Not on an in-the-truck dyno, and not on a "it just feels better" butt dyno. I don't know anybody who adds mods to their trucks/cars/motorcycles/boats to make more HP with less fuel and actually end up with better mileage. The claim that you have to put your foot into it less for the same power is nonsense, as everybody just puts their foot into it more for more power.

Also, the idea that driving the truck for 50-100 miles, then seeing a big difference in how it performs is flawed enough on its own, but doing that with two different injector sets many hundreds of miles apart and being able to objectively determine any difference is just not scientific at all. I'm not saying there isn't a difference, just that it should show up in the data somewhere. If the difference is real and is not showing up in the data, we aren't looking at the right data. That's the reality. If drivability is really better, there should be a metric.

If there is a round two, I really encourage a deep dive on this to isolate which data we should be looking at to confirm/reject that claimed difference in drivability. There was an attempt to get @dirtydeeds to suggest what data is needed, but he has yet to make a suggestion. I'm not suggesting he's being evasive—it may have just been lost in the banter. He clearly knows these engines, and I'd love to hear where he thinks the differences would show up.

 

[Travis Bickle]

Hopefully you all can stop with this ridiculousness now.

 

[I Lean]

Hopefully you all can stop with this ridiculousness now.

It seems to me like it stopped back in March, until you just bumped it back up?

 

[Oldsman71442]

Anyone else notice the vehicle outside air temp changed from 32 to 37 degrees over the coarse of the tests? Now i am an aircraft guy more than a car guy but I will say I know for a fact on airplanes 9 degrees of temp change is about 4.5% performance variation. I couldn’t open the file for data for some reason so maybe this was taken into account? Just curious everyone’s thoughts?

 

[suprarx7nut]

Anyone else notice the vehicle outside air temp changed from 32 to 37 degrees over the coarse of the tests? Now i am an aircraft guy more than a car guy but I will say I know for a fact on airplanes 9 degrees of temp change is about 4.5% performance variation. I couldn’t open the file for data for some reason so maybe this was taken into account? Just curious everyone’s thoughts?

I don't have the data pulled up (on my other PC) but we did an ABA style test where the 12-hole got first and last. The idea being that it would help mitigate the risk of that sort of transient variable leading to any false conclusions. If there was a temp difference over the course of the testing, the 12 hole should have gotten the first and last run, hopefully giving it a chance at both ends of the spectrum.

 

[pat27]

Using good gas always. Along with fuel system cleaner products like 44k, Chevron Techron, Seafoam, etc. occasionally. As well as the on-board cleaning systems, like Dealerships offer. Along with driving regularly. Are all good practices to keep fuel injectors happy.

But the best way to check for excessive leak-down and poor spray pattern. Is having fuel injectors tested, cleaned and rebuild.

When to Clean or Replace fuel injectors

Please post your experiences and thoughts on the subject. I’ve been considering cleaning or even replacing all 8 fuel injectors, is this wasting time and money. I understand keeping fuel injector clean by adding a can of additive to the gas tank, now & then, is a good practice. This keeps them...

forum.ih8mud.com

They make 16 hole fuel injectors now.. you should give those a try

 

[crimsonaudio]

Reading this thread reminds me of audiophiles who claim to hear things that aren't measurable but are 'plainly obvious if you'll just listen'...

Appreciate the data, @suprarx7nut !