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XR3Z's vs 19 XF2E's (2001 XJ) and so much more


NAXJA Forum User
First post, I thought I'd come to where the pros go..

Yup, another injector thread but mine is more specific in comparing these two particular EV6 for my 2001 JEEP CHEROKEE.

XR3Z 9F593 A4B #22.8 (240cc @ 43.5) Single hole injectors
#19 xf2e-c4b's ([email protected]) 5.0 Mustang 4 hole injectors

My Questions:

What are the trade-offs between the two when comparing them? What are the gains/losses and pros and cons with one vs the other? Ie. Fuel Efficiency, HP, etc

I've read countless threads and my brain is FRIED!:wow: Many of the threads I've read are either not vehicle specific (2001) or lose narrative as people bounce back and forth from different vehicle years or the thread gets hijacked by 30 other people.

Please don't hijack the thread and make it more confusing. Let's stick to the topic between these two specific I(EV6) injectors for a 2001 Cherokee XJ.

I am new to all this but have been learning as much as I can and have learned a lot but for this particular topic, I can't seem to find answers.

I'm not necessarily dead-set on either of these, but I’ve read several threads saying these 2 injectors are the best EV6 injectors for the 2001 Cherokee XJ regarding spray, fuel efficiency, and torque.

once I figure out which injector to choose from I’m either going to buy them used and refinish them with a kit or buy new.

-If used run a good can of good injector fluid through a tank of gas wit BGKK4

-check and clean two vents coming up off of valve cover (the ones that go to air vents to clean air, the other that goes to intake manifold.

One guy suggested:

"Are you dead set on running the SD injectors? The jtec+ ecu has a wide range of adjustment"

Huh? What??:wow:

In regards to the SD injectors and the JTech+ecu, What does he mean? Can someone clarify that? Does he mean buying a new map sensor and electronic controller and/or adjusting the fuel regulator? Electric tuners for ODB II?

I’ve also read a few say to “make sure the spacing/measurements are correct” Huh? :wow:

I just hope I’m doing all of this chronologically right and doing everything correctly.

Another concern is that I am doing this chronologically right.

before I install the injectors to the fuel rail I’m going to buy good new wiring and buy an adjustable Map sensor and controller then replace the filter with a new/good filter ie. Wixx, Mopar, or Napa gold.

I’ll be using Shell Rotella high miles Oil with high zinc. From the forum, many agree this is the best oil to use.

I just hope I’m doing all of this chronologically right.

Please understand much of this is Chinese to me but I love learning and reading about how to work on and improve my Jeep. I am trying to learn as much as I can possible and be a helpful member of the forum. I have become obsessed with all the XJ mechanics and am learning from scratch using NAXJA as a resource.
If I’m confused in any way please let me know. I’m just referring to my notebook that I’ve made writing everything down “to-do” from all the forum posts. I’m just having a hard time figuring this all out and trying to make sense of it. lord knows I’ve done my due diligence but I only know and understand so much. I've put countless hours researching how to better improve my nee XJ's performance and mechanics.

I am not rich either so this will be a slow journey for me but I am so excited. I will be doing the mods piece by piece in increments as I save up $. I want this truck to last the rest of my life and be something I'm proud of as I did it all myself.

As I said I am just here to learn and have taken this on as one of my life goals, Not playing the poor me card but may be important for you guys to know that I do struggle with Dyscalculia, Dyslexia, and ADD. So this can all be very hard/frustrating for me. it comes easier than others and unfortunately, I am not that guy. I have to read these things over, over, and over again just to get an idea of what's going on. The parts # F@ck me up big time and it can all be very frustrating at times..Lots of youtube too. Doesn't help that I am probably the most neurotic person you will ever meet:paperwork.

This will be a HUGE task and a long journey for me. If anybody would be so kind to help me out with any of this I would appreciate it more thank you know bc it's a somewhat hellish task for me trying to connect the dots.

Where do I start after the injectors?


*I plan on flushing and redoing the cooling system with new hoses.
Then new spark plugs (NKG's/ZFRN or E3's) and I will be replacing the wires for injectors and spark plugs.

After that,
*Get a programmer for better fuel economy

*I will build a cold air intake and relocate the intake temp sensors and make a DIY air box or air tube and run it to the grill area.

*Change all fluids including powering steering (drain and flush), change new coolant (drain and fill), brake fluid (drain and bleed then refill), and replace the transmission filter. Radiator fluid (drain and fill), Transmission fluid (drain and fill with AW$ pan +dexron/mercon, Rear differential fluid: mobile 1 synthetic gear LS 75w-90, Front differential Fluid: 80w90 gear oil

*Add engine additives: ZDDP + Marvey Mystery Oil + Seafoam+corrosion inhibitors+ detergents and dispersents

*water pump, Fan clutch, Serpentine belt

*Open Throttle Body and have it bored to something larger if neccessary.

*install tried and true upgrades:
CIA = S/C + tc to lose spongy weight :wow:

*Clean CCV system

*Change all RB and intake tubing

*Change rotors and caps

*fan clutch
-vacuum lines

my plan is to do as many mechanical mods as possible throughout this learning process to make her mechanically the best as possible and make a detailed thread of each mod. Fuel injectors are my first step on the journey.

I know this is a crazy long post but it'd about the injectors but I also wanted to give you my whole game plan...So any advice in addition to the injectors is welcome.

thanks again fellas.

Thanks, guys,

Sounds like you have a lot to learn about 4.0's and 2000-01 jeeps in general!
OK, I read through your list. And your XJ is a 2001. So, no cap and rotor or plug wires. Look into the Viper coil update. https://www.ksuspensionfab.com/store/c3/Jeep_Cherokee_XJ/MJ.html#/
I can't answer directly to your Injector question. I have replaced stock injectors with the Ford 4 holes. I could not feel any owner improvements or MPG increase. This was on two '89 XJs. II have done the 12 holes. Also, no improvements.
The link posted above is a good resource in RCP's post.
I run NGK spark plugs, the copper ones.
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On the oil, I run Shell Rotella. T4 10W-30, 10W-40 or the 15W-45 are good. Dello and I forget the other are good choices too. No need to add a Zinc pack if using a Diesel oil. I do try and use the Rotella T6 5W-40. I use NAPA Gold or Platinum filters.
I do bore out the TBs to 60mm. I do notice a bit of a performance in the inclines of mountains in WV. Also, I do have a 2.5 cat back exhaust and aftermarket headers.
I would say from your post, that you are after a bit better performance with a bit better MPG.
I would also look at brake and steering upgrades.
I wrote up a long response with multiple responses to many of your questions, but my phone died.

Welcome to the site, glad to hear your enthusiasm for the xj platform… however I think you are a little optimistic about fuel mileage. Xj fuel mileage is bad, and only gets worse. It’s a cardboard box with a heavy tractor motor from the 60’s in it. Fancy injectors don’t change that.

Fuel injector swaps are neither a modification, nor do they make power. This isn’t a vidya game, don’t treat your xj like it is one. If you don’t understand the difference between single hole and multi hole injectors, stop trying to deceide which to buy. Run the stock ones til you have a reason to swap away from the oem. It was designed by someone who understood those things.

Welcome. Bit slow down!