Injector upgrades?

[JeepCoMJ]

Has anyone done anything with their injectors? Not much info on it.

I'm not particularly interested in increasing lbs for injectors, while that will obviously be an over-thought idea most would have.

I'm basing my thoughts on this on simple principles: Single hole injectors do not atomize fuel as well as multi-hole injectors.

Example: Dodge neon srt4 injectors are rated much higher lbs. than the standard 96-01 4.0 injectors....and also have 5 hole spray pattern rather than single large hole spray pattern. The increase in atomization results in a decrease in unspent fuel, thus an increase in fuel mileage as well as performance. The kicker of that is that you do not even have to consider upgrading the fuel pressure regulator as you do not *need* higher lbs on a stock vehicle. Thusly, the injectors, while rated higher, will provide fuel at the same rate as stock, though better atomized.


I'm pretty sure I can simply use the neon srt4 injectors in my 3.7l KJ and it won't be a problem. They are (from memory) the same height and diameter as the 3.7l injectors. What I'm unsure of is wether or not this will cause issues with the ECM.

Thoughts?

-Pat

 

[Porkchop]

I have always wondered the same thing did this on my ZR2 with the spider injector upgrade and it did make a difference so have wondered if it could be done on the single injectors for the 3.7

 

[JeepCoMJ]

I think I'm just gonna do it. I still have 2 spare rebuilt neon srt4 injectors from the two junkyard ones I robbed them off of before rebuilding them. Really just have to buy a "full set" for an Srt4 now and I can dump them in in a matter of 15 minutes or so.


I really think this is an oversite and overthought by most. Upon reading "performance upgrade" ideas for KJ's....people point out "do the simple stuff....plugs, tuner, gears"

Plugs should be coppers. Autolite platinums may work nice. But nowhere in that "simple" upgrade stuff is something as "simple" as upgrading injectors.


With these injectors in my 99 xj, on a 4.6 stroked motor that I built with comp. torquer cam, 00+ intake mani, borla header and s pipe, 62mm tb, ax15 5 speed, nv242 I pulled 23/24mpg regularly. before these injectors, all I could get was 21mpg.

 

[Porkchop]

The suspense is going to kill me til you get time to do this. Guess I don't have the cahonas or the extra cash to try it.

 

[JeepCoMJ]

The suspense is going to kill me til you get time to do this. Guess I don't have the cahonas or the extra cash to try it.

Junkyards by me charge base price for injectors. it's cheap. injectors are easy to rebuild, with the right tools, and flow test is also easy to build if you have a mill/lathe.

I'll do it soon. And I'm planning on buying enough for two KJ's since there are two here...test on one, then execute.

 

[twack]

correct me if i am wrong ( i come from tunning talons/eclipses) but if you drop in a higher lbs injector it will flow more at the same injector pulse then a stock injector, so you would run really rich and waste gas and get less performance, unless you had some piggy back fuel computer. At least thats how talon motors are, and i didnt think that the 3.7 ecu could tune itself for bigger injectors. i might be wrong but thats what it thought, hence why no one drops bigger injectors in our cars

 

[JeepCoMJ]

correct me if i am wrong ( i come from tunning talons/eclipses) but if you drop in a higher lbs injector it will flow more at the same injector pulse then a stock injector, so you would run really rich and waste gas and get less performance, unless you had some piggy back fuel computer. At least thats how talon motors are, and i didnt think that the 3.7 ecu could tune itself for bigger injectors. i might be wrong but thats what it thought, hence why no one drops bigger injectors in our cars

Injectors are only going to use the pressure supplied to them. Computer in an xj will lean it out to adjust for the fact that more volume (not pressure) will be used, negating the extra fuel spent.

That is why I want to do this to the KJ. But no info on ECM capabilities, zero discussion on the subject

 

[wlfpck]

Necro'ing an old thread...

Has there been any update on this?

Will upgrading the fuel injectors to a better dispersion pattern increase mpg?

Apparently some people are having good results?

LOST JEEPS • View topic - Injector upgrade for the 4.0L, $139 for all six injectors

 

[Rich75043]

Necro'ing an old thread...

Has there been any update on this?

Will upgrading the fuel injectors to a better dispersion pattern increase mpg?

Apparently some people are having good results?

LOST JEEPS • View topic - Injector upgrade for the 4.0L, $139 for all six injectors

https://precisionautoinjectors.com/collections/jeep-injectors/products/bosch-3rd-generation-4-hole-upgrade-fuel-injectors-for-2002-2007-3-7l-engines
you could try these?

 

[wlfpck]

I may give this a shot. Seems like it's worth while.

Kinda worries me that they only have them till they're out of stock. You think the SRT4 neon ones would work as well? Apparently those are SUPER cheap.

 

[Rich75043]

no idea but they do have them all over fleabay as well. was thinking about picking some up when I saw this thread...maybe someone more knowledgeable than I will chime in.

 

[wlfpck]

Yeah... was hoping someone did this already and would have some input.

 

[BillyG]

I started thinking about this as well and when I check the Bosch replacement injectors for a 2007 Liberty, it already has 4 holes.

https://shop.advanceautoparts.com/p...or-62389/11481407-P?searchTerm=fuel+injectors

 

[Casey.N]

Necro'ing an old thread...

Has there been any update on this?

Will upgrading the fuel injectors to a better dispersion pattern increase mpg?

Apparently some people are having good results?

LOST JEEPS • View topic - Injector upgrade for the 4.0L, $139 for all six injectors

i swapped to a 12 hole injector, went from 15mpg to 12 but have a significant increase in throttle response, at the end of the day not worth it.. for me kinda was considering i see 6krpm daily and dont give a F*** about mpg's

 

[Casey.N]

these are the 12 hole injectors i got

https://www.ebay.com/itm/Best-Upgra...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

 

[Bill chase]

Without the ability to alter fuel trim in the ecu I would not mess with it. It's programmed with the original equipment injectors and their spray patterns, lbs per hour flow rate etc in mind.... by altering that you could be introducing an injector that injects too much fuel and the short and long term trims might be unable to compensate for the difference.

 

[wlfpck]

Hm.... fair enough. Was reading on it with the XJ's and some people were pushing this pretty hard as a great mod. Figured I'd ask for the KJ.