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i have looked for injector flow rates in the ROM without finding anything. As the car is running open loop without O2 sensors I thought it would be best to compare to spec rather than just checking that they delivers same amount.
i suppose someone on here here might know ?
Engine is an 88 5.3 Lucas-ignited V12 from an English XJ12
I was told its 210cc per injector if 'new' you can always ask the guy in florida who fixes them, might be slight differences between HE/flat engine? My 89' has an avg 208cc with a 1.68% variation between all.
210cc per minute at 30 PSI fuel pressure with constantly open injector will be what I compare against then. Thanks!.
I have HE engine in my PreHE car, so The 210cc should be good.
Leo
Last edited by leo_denmark; 01-26-2019 at 02:55 PM.
That would be 107.3 cc @ 43.5 psi if my conversions, fuel density table and math is right. That’s pretty far off VancouverXJ6’s figure.
Fuel density must be less than 1, so I think you might have inverted the calculation ?
if that is the case, then the result is 191.6 cc and thereby not that far off.
It seems 3 bar is the default pressure for these measurements.
Fuel density must be less than 1, so I think you might have inverted the calculation ?
if that is the case, then the result is 191.6 cc and thereby not that far off.
It seems 3 bar is the default pressure for these measurements.
Hmm, 191 vs 208-210? Will have to wait for others to chime in. I'm just quoting Jaguar fuel Injector service, as per our discussions when my set of 12 were refurb'ed 210 was about OEM spec, my set came out at 208 after two cleanings
Last edited by VancouverXJ6; 01-26-2019 at 04:58 PM.
Hmm, 191 vs 208-210? Will have to wait for others to chime in. I'm just quoting Jaguar fuel Injector service, as per our discussions when my set of 12 were refurb'ed 210 was about OEM spec, my set came out at 208 after two cleanings
Actual flow rate cannot be too important as long as you have O2 sensors. Pulse lengths will be adjusted while you are running in closed loop. I have seen the 210cc number somewhere before, but that could of course be from you as well...
I’m on the other hand running open loop all time and ECU is therefore just assuming the injectors delivers correct amount.
I do not expect it to be too bad though, as the car was running well and is not using that much fuel.
What I have is a slightly irregular idle, and I suspect that to be due to either a few injectors delivering too little or leaking a bit.
My cleaner/tester unit does not have a test, where I can test flowrate with constantly open injector, so I'm not going to be able to compare against the constant flowrate.
I have tested in 3 conditions: Idle, medium and fast. The manual tells that idle is 750 RPM, but does not tell what medium and fast is. Upper limit is 7500 RPM, but I don't think it's going that high.
I ultrasonic cleaned all injectors 10 minutes before testing as I didn't want to get too much dirt in the test fluid.
Results were quite consistant except from the injectors from 1A and 1B, which flowed a bit more. I had an idea they were different flowrate, but I have afterwards found that that is probably due to injectors being delivered with hoses mounted.
One of the other injectors flowed quite low in the high speed test, so I cleaned that one together with 3 other from the lower end.
Now fun started as this resulted in only minor improvement on the one with low flow, but now the 3 other flowed as much as the 1A and 1B.
No way back, so I have cleaned, measured and sweared until I now have fairly consistant flow volumes in the 3 tests I run.
The spread is up ±10%, but this includes reaction time for the opening as well and should in my opinion not be compared to the static flow rate spread. Still I'm not too happy about the outcome as I had a similar spread after initial clean and test, just with lower average flow rates...
as usual i do things different , after studying my needs , i ordered new, 12 Bosch injectors, flowed at 43psi to 220 cc min. all within 1%.
then i adjust fueling needed using an AFR gage, it does take time and many drives , but once set! i lock settings in to ECU! i can also make small adjustments fuel mixture by readjusting fuel perssures!. fuel map programer used in car,driving or dyno!
I love what you have done to your car.
Could you reveal how much variation you normally see in flowrates, when you test pulsating injectors rather than the static opening.
I have a feeling that the opening/closing charateristic of the valves will have an impact, when pulse lengths are as short as 3 ms. That is what I used for my tests. It was the default setting, and I had no real idea about how long injectors normally stay open anyway...
well what i found when testing, full open static tests can vary some,compared to pulsed injections, of course you try for the best balance between all the injectors,especially used ones!
most injectors can wear slightly with hi milage parts! and not all new ones may be spot on, and speed of pulse may vary the final volumes CC.
also pre injectors flow more than HE stock, they compansated by changing pressure for better atomization!
for that reason is why i went with a standalone system, but i agree that may be not for everyone, its time consuming and costly!
ok after 10yrs of testing ,most street driven engines can handle a vary of up to 5% without much problem, for a serious race engine running at full output limits, need as close as you can get like 1% or less!
that said , i do think the factory HE engine are running much to close to the edge of DETONATION, the cure would be to richen up the mixture thru the complete ECU map ,idle to wide open hi rpm throttle!
dyno will be needed for those tests.
i have heard that some of the temp sensors can be fooled into thinking the engine is cool, so ecu increases fuel signal time! they use a resistor or other ways!
like cooler thermostats, personally i'm kinda old fashioned i like my engines running around 180*F, 195/200F is to close to boiling point!
hope this can help, if i remember more i'll post it up!
ron
Leo
The injectors fitted to the 5.3 are Bosch 0 280 150 163 see post 22 below (also known at the time as Lucas 73178A).
The attached link goes to a chart that shows the flow rate for this injector at 3 bar (remember it runs at 2 bar in the engine). It is the 8th line of data line on the chart. InjectorRatesBosch
Greg
Last edited by Greg in France; 01-28-2019 at 04:15 AM.
well what i found when testing, full open static tests can vary some,compared to pulsed injections, of course you try for the best balance between all the injectors,especially used ones!
most injectors can wear slightly with hi milage parts! and not all new ones may be spot on, and speed of pulse may vary the final volumes CC.
also pre injectors flow more than HE stock, they compansated by changing pressure for better atomization!
for that reason is why i went with a standalone system, but i agree that may be not for everyone, its time consuming and costly!
ok after 10yrs of testing ,most street driven engines can handle a vary of up to 5% without much problem, for a serious race engine running at full output limits, need as close as you can get like 1% or less!
that said , i do think the factory HE engine are running much to close to the edge of DETONATION, the cure would be to richen up the mixture thru the complete ECU map ,idle to wide open hi rpm throttle!
dyno will be needed for those tests.
i have heard that some of the temp sensors can be fooled into thinking the engine is cool, so ecu increases fuel signal time! they use a resistor or other ways!
like cooler thermostats, personally i'm kinda old fashioned i like my engines running around 180*F, 195/200F is to close to boiling point!
hope this can help, if i remember more i'll post it up!
ron
Hi Ron
I will not be racing or going 130 MPH for hours, so I'm not too worried about the impact of the variations, I find.
I have measured a 3-4% increase in average flow in idle and medium pulse speed and +7-8% at high pulse speed, and that cannot be bad based on your opinion on the engine running too lean, as I run open loop and thereby actually will get the increased fuel flow.
What annoys me is that I cannot get all of the injectors with low flow to react on cleaning. I started with 9 injectors being quite close in flowrates + 2 high and one low. Now I have a more even spread between high and low and a general increase.
Regarding the very low spread on static injector flow both you, Warren and Vancouver mentions: I would like to challenge the measuring system accuracy. Fuel pressure and flow rate need to be measured pretty exactly to be able to measure within 0.1%, which I would suggest as recommended measuring system accuracy to claim measuring the parts to be within 1%. It will help if they run the 12 injectors together on comon pressure, but I doubt most places have machines for more than 8 injectors.
I can for sure not measure that exact on my machine. Volume graduation is 2cc on 140 cc cylinders and can be read with maybe 0.5cc accuracy. Fuel pressure meter has 0.2 bar graduation, I can maybe read and adjust within 0.05 bar. Timing is most likely very exact though. I see variation up to ±2% when I run same injector twice...
Anyway: I do now know that all injectors are tight and that they all work at all speeds. I bet the spread is not worse than before, and the increased flow wiill cause my engine to run less lean. No too bad after all.
Leo
Just in case you did not know, on the 16CU ECU (which you should have) there is a trim adjuster to richen or lean the engine, which can be used to make it happy at tickover.
Greg
Leo
The injectors fitted to the 5.3 are Bosch 0 280 150 163 (also known at the time as Lucas 73178A).
The attached link goes to a chart that shows the flow rate for this injector at 3 bar (remember it runs at 2 bar in the engine). It is the 8th line of data line on the chart. InjectorRatesBosch
Greg
Thanks Greg
Edited according to post 22. This is not going to be easy to read in 3 years from now !
BOSCH NUMBER LBS/HR CC/MIN GRAMS PSI BAR
0-280-150-163 - 17.2 - 180.8 - 130 - 43.5 - 3
That was one more differing number on flow rate
Leo
Last edited by leo_denmark; 01-28-2019 at 04:56 AM.
Leo
Just in case you did not know, on the 16CU ECU (which you should have) there is a trim adjuster to richen or lean the engine, which can be used to make it happy at tickover.
Greg
I know, but I haven't found and touched it yet. Does it only adjust the idle mixture ??
I know, but I haven't found and touched it yet. Does it only adjust the idle mixture ??
BR Leo
It is on the side of the ECU, and looks like a small hole with a D shaped rod in it. You need a bit of tube just big enough to go over the rod and not so big (or so thick a wall) it will not then go down the hole! A 1962 Massey Ferguson 35, 4 cylinder diesel tractor fuel pipe is ideal! you then just crush the tube on one side slightly so it engages with the D, and it clicks one way or the other to change the mixture slightly. This adjuster does make a noticeable difference to the engine note at tickover. I do not know for sure, but I expect what it does is change the mixture slightly over the entire fuel map, maybe one of the electronic wizzes will be able to confirm of deny this?
Greg
01-26-2019, 01:05 PM
Injector flow rates
