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  #31  
Old May 2nd, 2018, 13:08
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alexgalexg alexgalexg is offline
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Re: Problems after 12 hole injection upgrade

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Originally Posted by kastein View Post
There is zero data out there to support any of the claims made concerning 12 port injectors. None. Aside from people's butt-dynos, and I've never been shown the NIST calibration stamp on a butt dyno so I don't trust them, especially given people are generally comparing brand new chinesium 12 port injectors vs their multi hundred thousand mile, multi decade old gunked up factory injectors.

Every time I have pressed Raffi about dyno testing his injectors he has evaded the question and not actually done it. The original claim was they make more power and low end torque. Then they were claimed to improve idle and throttle response. Then fuel economy. Every time something does not pan out or people ask for proof of things that the sellers know is not possible, the goalposts change.

I will believe it when someone proves - comparing new 1 or 4 hole injectors to new 12 hole - ANY of the above claims, using actual, calibrated test equipment and rigorous testing procedures. Until then it is bullshit and the sellers are just making money off of the uninformed masses by selling chinesium injectors.

A sucker born every minute.
Well I would like to do an injector upgrade on my 98 4.0. I'd you have a link to some nice injectors that DO improve the way my engine runs and wont make it run rush or lean then please do comment here. If the replacements in the mail dont work I'd like to get something and soon. This little situation is forcing me to drive my 300,000 mile project xj with one shock broken in the rear and only front brakes since now my daily is down

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  #32  
Old May 2nd, 2018, 14:36
dktool dktool is offline
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Re: Problems after 12 hole injection upgrade

About 3 years ago I put a set of cleaned / flow matched 4 hole injectors in my 180k'ish '98, just recently I was going through my cabinet of parts and found the oem 1 hole take offs, I was bored and figured what the hell, let's do a test.

I put those uncleaned 1 hole injectors with 180k on them back in my pile and guess what ? no difference on the Ass Dyno idle quality or mpg.

My engine is 100% stock, so YMMV if yours is modified.
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  #33  
Old May 2nd, 2018, 15:04
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kastein kastein is offline
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Re: Problems after 12 hole injection upgrade

Remember that OEMs are, and have been, behind the 8 ball when it comes to emissions (higher emissions = inefficient combustion = lower engine power for given amount of fuel used) and fuel economy (again, more gas for less useful work) for decades. Changing from one nozzle style to another on an injector is a very very low cost change for them when they buy millions of units per year. If they could improve any of the factors people claim 4 and 12 hole injectors improve by changing out the injectors, they would - auto companies would gladly slap their own grandmothers if it meant their CAFE numbers went up by even 1mpg or it meant they could eliminate more expensive components required to make an inefficient engine pass emissions.

Some engine designs may require it... it doesn't seem to me like ours need it. Unless someone's got evidence and facts to prove it.
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  #34  
Old May 2nd, 2018, 15:24
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Problems after 12 hole injection upgrade

With these it definitely has less harshness to it. At the least. I'm mostly in the market because two of my injectors are of different age (came out of a vehicle with 100k less miles on it). I'd like to have a nice new set. Figured why not do an upgrade while I'm at it. Regardless I dont want to use the set I just pulled out. Would go for new OEM ones before I put these back in

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  #35  
Old May 2nd, 2018, 16:08
RCP Phx RCP Phx is offline
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Re: Problems after 12 hole injection upgrade

I would suggest a oil test with these new injectors, I think their probably washing the cylinders.
If you want the # for a set of 4-hole injectors that did work - 0 280 156 077 !
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  #36  
Old May 2nd, 2018, 16:16
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alexgalexg alexgalexg is offline
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Re: Problems after 12 hole injection upgrade

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Originally Posted by RCP Phx View Post
I would suggest a oil test with these new injectors, I think their probably washing the cylinders.
If you want the # for a set of 4-hole injectors that did work - 0 280 156 077 !
What is this number? Do I Google it or search it into a specific parts site?

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  #37  
Old May 2nd, 2018, 16:24
RCP Phx RCP Phx is offline
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Re: Problems after 12 hole injection upgrade

That is the number. I purchased them here........
https://precisionautoinjectors.com/p...p-4-0l-engines
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  #38  
Old May 2nd, 2018, 18:14
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Re: Problems after 12 hole injection upgrade

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Originally Posted by RCP Phx View Post
That is the number. I purchased them here........
https://precisionautoinjectors.com/p...p-4-0l-engines
Thanks. If my warranty replacements dont work I'll look at these

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  #39  
Old May 3rd, 2018, 07:57
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Re: Problems after 12 hole injection upgrade

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Originally Posted by RCP Phx View Post
That is the number. I purchased them here........
https://precisionautoinjectors.com/p...p-4-0l-engines
And these will not make my engine run lean or rich?

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  #40  
Old May 3rd, 2018, 08:06
RCP Phx RCP Phx is offline
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Re: Problems after 12 hole injection upgrade

They ran perfect in my non-modified 2000 XJ 4.0!
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  #41  
Old May 7th, 2018, 17:40
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alexgalexg alexgalexg is offline
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Problems after 12 hole injection upgrade

Ok guys little update I put in my warranty replacement 12 hole injectors today. Still bucks under load in 4th and idles with a miss. Neither of which happened after I put the original injectors back in earlier today.

So these did not work I my 98. In the meantime he sells 4 hole I injectors and I got some good advice here for injectors as well.

Injectors are a crucial part of a car and I drive my xj on very long road trips often. It is crucial that my new injectors are as reliable as the originals which I have never had an issue with. I will be looking into some of the recommendations above and doing some research over the next week.

I will make a final update with what I chose and how well they run in my jeep. Thanks to all that helped

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  #42  
Old May 7th, 2018, 21:39
dktool dktool is offline
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Re: Problems after 12 hole injection upgrade

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Originally Posted by alexgalexg View Post
It is crucial that my new injectors are as reliable as the originals which I have never had an issue with.
Sound like you exactly which ones to buy.
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  #43  
Old May 7th, 2018, 21:40
dktool dktool is offline
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Re: Problems after 12 hole injection upgrade

Sounds like you know exactly which ones to buy.
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  #44  
Old May 8th, 2018, 07:03
HH-Bham HH-Bham is offline
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Re: Problems after 12 hole injection upgrade

Thanks for the update. Good information to have.
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  #45  
Old February 20th, 2019, 14:38
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alexgalexg alexgalexg is offline
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Re: Problems after 12 hole injection upgrade

Long, long time later update:
So im actually selling these injectors off. People complain they dont work in Jeeps so I was planning on advertising them by spec, not for any specific vehicle.



I tracked the injectors down ignoring the ksuspension website all together. They are Bosch and the specs are only slightly different than oem aside from how the fuel is atomized with 12 holes vs single hole.

The specs are as followed:
43.5psi
22.8lb/hr
12 ohm


So im not entirely sure why they caused a miss at idle and bucking under load since 96+ used 49 psi and 21 lb/hr. Am I missing something here? Slapped the oem ones back in and it doesnt buck or miss at idle.
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