Installing 19# injectors on 97 XJ

Double Down · May 27, 2004

If I am right, my current 97 XJ injectors puts out about 18.6#/hr, but I have heard that there is no need to jump up to the 24# unless you have a stroker...but I was told the 19# is a good upgrade because you get a much better flow, etc.

First, is this worth it and true?

Second, if the answer is yes, what do I need to know in order to do the install? Does it matter what kind of Ford 19# injectors I get? How do I do the install, do I need to change anything after they are installed (restart computer, calibration crap, etc.)

Thanks,

Chris (Double Down)

wascobi · May 27, 2004

I installed the ford/bosch #19 on my '90 and it has been one of the best upgrades for the dollar to date! way smoother idle, pulls easier in the bottom end. just better running overall! got mine at www.fiveomotorsport.com comes with new o-rings ready to bolt in. just make sure to disconnect the battery, release the pressure on the fuel rail, and swipe a dap of vaseline around the o-ring to install. it will run like crap untill the air is displaced by fuel.

Double Down · May 27, 2004

Sounds good, but I am wondering if it is the same or worth it on the 97 model?

Also, since I'm kinda new to all of this, how do you release the pressure on the fuel rail?

Thanks,

Chris

JeepFreak21 · May 27, 2004

To release the pressure, there is a little cap about half way down the rail. Unscrew the cap and press in the shrader (sp?) valve. I've heard that Vaseline will ruin the O ring over time, I believe some other lubricant is advised.
Billy

wascobi · May 27, 2004

on my '90 there is a tire valve type fitting at the front of the fuel rail. release the fuel pressure( along with a little fuel) just like releasing tire pressure.after the battery is disconnected of course. the fuel rail unbolts as one piece. five0 has a link on how to install injectors. dont forget to install a new fuel filter to keep the new injectors clean. this is the time to do it while the pressure is off. as for the vaseline,thats your call. proper fuel o-rings are resistant to petrolium products. regular rubber ones are not.

Ed A. Stevens · May 27, 2004

Double Down said:
If I am right, my current 97 XJ injectors puts out about 18.6#/hr, but I have heard that there is no need to jump up to the 24# unless you have a stroker...but I was told the 19# is a good upgrade because you get a much better flow, etc.

First, is this worth it and true?
Chris (Double Down)

It's a 97'? ... NO!

The 97's have the return-less fuel rail, and run at 49 psi (IIRC). I believe they are rated at ~23 #/hr @ 49 psi.

Now, an 87' runs 18.7 #/hr at 39 psi, and will benefit (slightly) from a 19 #/hr FMC injector, a benefit from the four spray pattern pintle (tip).

Dr. Dyno · May 27, 2004

Double Down said:
If I am right, my current 97 XJ injectors puts out about 18.6#/hr, but I have heard that there is no need to jump up to the 24# unless you have a stroker...but I was told the 19# is a good upgrade because you get a much better flow, etc.

First, is this worth it and true?

Second, if the answer is yes, what do I need to know in order to do the install? Does it matter what kind of Ford 19# injectors I get? How do I do the install, do I need to change anything after they are installed (restart computer, calibration crap, etc.)

Thanks,

Chris (Double Down)

Your stock injectors flow 23.3lb/hr at 49psi so it would be a very BAD idea to swap in Ford 19lb injectors. Keep the ones that you have if they're OK. They are fine and you won't need higher flowing injectors unless you've done substantial performance mods and your engine's running lean.

Eagle · May 27, 2004

What Dr. Dyno said.

Be careful extrapolating info from posts not repated to your vehicle. There are three or four distinct variations on the 4.0L engine. 87-90 (non-HO) used the 18.6 pound injectors. Early HO (91 - ??) used 22 pound, IIRC. Somewhere in there they increased the injector size again. Then in 2000 they changed to the direct coil ignition, and I don't know if there was another injector change at that time.

JeepFreak21 · May 27, 2004

wascobi said:
...as for the vaseline,thats your call. proper fuel o-rings are resistant to petrolium products. regular rubber ones are not.

OK, that's where my confusion came in I think.
Thanks,
Billy

Double Down · May 27, 2004

Thanks all, glad you guys caught that...

Chris (Double Down)

Dr. Dyno · May 27, 2004

Eagle said:
What Dr. Dyno said.

Be careful extrapolating info from posts not repated to your vehicle. There are three or four distinct variations on the 4.0L engine. 87-90 (non-HO) used the 18.6 pound injectors. Early HO (91 - ??) used 22 pound, IIRC. Somewhere in there they increased the injector size again. Then in 2000 they changed to the direct coil ignition, and I don't know if there was another injector change at that time.

Yes there was: '87-'90 engines have injectors flowing 18.6lb/hr at 39psi, for '91-'95 it's 21.0lb/ht at 39psi, for '96-'98 it's 23.3lb/hr at 49psi, and for '99+ it's 22.5lb/hr at 49psi.
For the full injector lowdown (and a few other tech tidbits), go to http://www.jeep4.0performance.4mg.com/tech_specs.html

Yucca-Man · Jun 3, 2004

Let me make sure I've got this straight then before I place my order. I've obviously got a leak based on the photo below, right?

These are grey-bodied injectors, and according to Dr Dyno's link:
'96-'99, .......p/n 53030778, ...Grey, .........49psi, ............23.2lb/hr static flow
Since this is on a stock 4.0L (with only 168,500 miles)

So which ones do I order? Bosch 0280150556 D5B-19lb*, or Bosch F5TE-C1A*-24lb ??

Dr. Dyno · Jun 3, 2004

Yucca-Man said:
So which ones do I order? Bosch 0280150556 D5B-19lb*, or Bosch F5TE-C1A*-24lb ??

Get the 24lb Bosch units from http://www.fiveomotorsport.com/Injector_SetsJEEP.asp

Yucca-Man · Jun 3, 2004

Thanks Dr D - that's what I was thinking but wanted to get some clarification. That's the link I was looking at, and forgot to include it in the post anyway.

89xj · Jun 3, 2004

Yucca-Man said:
Let me make sure I've got this straight then before I place my order. I've obviously got a leak based on the photo below, right?

These are grey-bodied injectors, and according to Dr Dyno's link:
'96-'99, .......p/n 53030778, ...Grey, .........49psi, ............23.2lb/hr static flow
Since this is on a stock 4.0L (with only 168,500 miles)

So which ones do I order? Bosch 0280150556 D5B-19lb*, or Bosch F5TE-C1A*-24lb ??

for a cheap half assed cure, have you tried to twist/turn the injector back and forth. this may help seat the oring unless it is totally shot.

Yucca-Man · Jun 3, 2004

Murphy's Law tells me that I have just as good a chance of shredding the o-ring if I do that. I have a cracked exhaust manifold that I'm also shopping for a replacement, and the combination bothers the crap outta me right now. Replacing both sounds like the best available option to me...thanks though.

Jim

ryurabbit · Jun 3, 2004

So if I wanted to install 95 Jeep 5.9 injectors on my 92 4.0 would I have to change anything else or what would be the best combination of components to take advantage of a richer fuel system for somewhat more power. Maybe a stage 1 cam?

Installing 19# injectors on 97 XJ

Double Down

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