Topic: Stock injector rating in CC's

[FourbangerYJ]

I have been looking all over the net for what rating in CC's the stock F.I. P/N 53007232 the charts I have seen do not list any ratings. I have seen it in pounds per hour which I believe is 17.4

[sharpxmen]

I have been looking all over the net for what rating in CC's the stock F.I. P/N 53007232 the charts I have seen do not list any ratings. I have seen it in pounds per hour which I believe is 17.4

17.4lb/hr=183cc/min

i could not find the stock 4banger injector rated anywhere either other than here and another 4wd site

[FourbangerYJ]

17.4lb/hr=183cc/min

i could not find the stock 4banger injector rated anywhere either other than here and another 4wd site

  Thanks!

I am trying to compare injectors using this chart http://www.justfuelinjectors.com/servlet/the-template/efiflowchart/Page
I had no idea there were so many injectors out there.

The ones I have are Bosch P/N 0280155710 or 700(last 3 digits) they are rated at 18.25#per hour and 191.8 CC per min.
The Accel P/N 150X19 are 19# per hour and 199.7 CC. But these are about $45@ new. Not many used ones on the market.
Lucas has a 5201200 (not sure of connector type) 19.5 # per hour and 204.9 CC I have not checked price on these.

I am wondering how much the added holes for better spray pattern add to the improved performance? Looking at the #'s there is not alot more fuel going in with these injectors.

[sharpxmen]

Thanks!

I am trying to compare injectors using this chart http://www.justfuelinjectors.com/servlet/the-template/efiflowchart/Page
I had no idea there were so many injectors out there.

The ones I have are Bosch P/N 0280155710 or 700(last 3 digits) they are rated at 18.25#per hour and 191.8 CC per min.
The Accel P/N 150X19 are 19# per hour and 199.7 CC. But these are about $45@ new. Not many used ones on the market.
Lucas has a 5201200 (not sure of connector type) 19.5 # per hour and 204.9 CC I have not checked price on these.

I am wondering how much the added holes for better spray pattern add to the improved performance? Looking at the #'s there is not alot more fuel going in with these injectors.

actually the 18.25lb/hr flow less than the 17.4 stock ones, the reason is b/c the rating is at different pressure (18.25 at 43.5psi and 17.4 at 39psi) - equivalent the -700 rated at 18.25 would flow 17.28 at 39psi (or 181.62cc/min), the difference is minimal however. The spray pattern and atomization is better on these but at wot high rpm is less noticeable, it is more significant at low to mid range when air speed thru the intake is lower - so cruising you would get a bit better mpg and probably a bit increase in torque, not so much top end power (could be less by a hair).

the Accels are actually rated at 19.2 which is 18.18lb/hr at 39psi which translates to 4.5% increase in fuel delivery at wot and seems right for matching a larger t/b and a high flow filter (but best to use a wideband O2) - that would in turn result in about 5HP gain using 120HP baseline for the stock YJ, but i believe the numbers are a bit better since the YJ was underpowered from factory and there is some MAP compensation as well (my best guess with this mod you would be somewhere between 130 and 135HP).

you could achieve the same result by increasing the fuel rail pressure by 4 psi to a value of 43psi at wot using the stock YJ injectors or you can go with both (larger injectors and adjustable FPR) to fine tune your Air/Fuel ratio at wot (when the pcm is in open loop and not using the O2 feedback)

Jeffy updated the Fuel Injector FAQ with a post i had where the pressure/flow relation is explained here: http://4bangerjp.com/forums/index.php/topic,3479.msg52986.html#msg52986
have a read - there's also a table in the second post that show the flows for some common injectors for comparison.

[FourbangerYJ]

I find all this very interesting. I don't know Jack about this stuff so I get  pretty easy....(don't judge me)
It seems there are a number of people on this board that have done 19# F.I. swaps. They seem to be happy with the results. I don't know what the P/N is of those injectors. To my knowledge they are all design II and III that are from Ford's. It seems odd that they have enjoyed the swaps even thou your saying it's the same or less than the OE stuff.

I really don't want to mess with a FPR. I want to keep things simple, less to go wrong...I think you know what happens when I start upgrading parts that aren't broke

On the wideband O2 sensor. Can this be used with a mild build? What is the advantage of the wideband?

At what point is there to much fuel from the injector upgrade and it runs rich?

[Jeffy]

Jeffy updated the Fuel Injector FAQ with a post i had where the pressure/flow relation is explained here: http://4bangerjp.com/forums/index.php/topic,3479.msg52986.html#msg52986
have a read - there's also a table in the second post that show the flows for some common injectors for comparison.

Actually, I was going to address a lot of that but didn't have the time to sift through all of the info I had gathered.  It was the only glaring hole in the how-to though.

The company I know of that makes an adjustable fuel pressure regulator is JET.  It's for the 4.0L but should work for the 2.5L as well although it shouldn't be necessary with these injectors.

A wideband O2 sensor is just that.  It's able to see a wider band then the stock ones.  This allows you to fine turn the air/fuel MAPs if they are way off.  You can use a OE to look at the ratio since you're not going too wild.  I think JET also makes a reader for OE applications.  Still I wouldn't think that you'd be that far off.

Really, I think either the connections weren't good or the one or more  of the injectors themselves may have been bad.  Might be worth a try to borrow someone elses injectors which are known to be working or else have them checked.

Jeeps run lean normally.  You can really tell this when WOT.  I doubt you can really go too big unless you really go big.  The PCM should be able to adjust to an mild increase or decrease in each shot depending on what it's sensing from the O2.

[sharpxmen]

Actually, I was going to address a lot of that but didn't have the time to sift through all of the info I had gathered.  It was the only glaring hole in the how-to though.

The company I know of that makes an adjustable fuel pressure regulator is JET.  It's for the 4.0L but should work for the 2.5L as well although it shouldn't be necessary with these injectors.

A wideband O2 sensor is just that.  It's able to see a wider band then the stock ones.  This allows you to fine turn the air/fuel MAPs if they are way off.  You can use a OE to look at the ratio since you're not going too wild.  I think JET also makes a reader for OE applications.  Still I wouldn't think that you'd be that far off.

Really, I think either the connections weren't good or the one or more  of the injectors themselves may have been bad.  Might be worth a try to borrow someone elses injectors which are known to be working or else have them checked.

Jeeps run lean normally.  You can really tell this when WOT.  I doubt you can really go too big unless you really go big.  The PCM should be able to adjust to an mild increase or decrease in each shot depending on what it's sensing from the O2.

The only problem is that with a narrow band you won't know how rich you actually run, will give you the same info whether you're at 10AFR or 14AFR will still return 0.95v or above that - there is no way to tell how rich you are other than the fact that your AFR is below the ideal 14.7. Same for lean condition, but that's a spot you want to keep out of anyway so in that case it doesn't matter.

The PCM won't adjust anything when is in open loop, in closed loop however it will always target 14.7 and will re-learn and adjust to target 14.7AFR so the fuel trims are minimal - so when you're at wot and trying to make max power is where you actually want to tune your AFR, for closed loop it won't matter as the PCM will readjust based on O2 feedback (you can trick that too, but i don't think there's much benefit unless you run forced induction of some sort or if you really want to tweak you power range better and not care about mpg).

[FourbangerYJ]

I'll prolly try and clean up the ones I have and see what that does. But according to Sharp they are not a improvement over the OE ones.

The reason I was worried about running to rich is, the last time I was SMOGGed I passed by >< this much on my 02's. Maybe replacing my 02 sensor will be needed next time around?

[FourbangerYJ]

What is the purpose of the pintle caps?

[sharpxmen]

What is the purpose of the pintle caps?

apparently to reduce deposits. Some say that some pintle caps are also meant for spray pattern/distribution but i'm not sure about the differences in design for that, some injectors don't have a pintle cap at all (my Accels don't have one but they do have a tri-nozzle plastic insert and it looks to me that is meat to spread the pattern away from center). Some also hold the o-ring in place but on the intake manifolds i've seen the o-ring would not be able to come off anyway.

So to summarize my understanding is: to reduce deposits on the pintle or nozzle(s) and maybe for the spray pattern (not sure on this one but also depends on the cap design).