upandcoming

iTrader: (20)

Help!!!! I put in some bosch III's in my 89 305 and it will not stay running unless I unplug the Maf...when I do it will stay running...I dont understand it..I have searched the boards and I cant find a definate answer on this.. I changed maf's with a running gta and the same thing.

TKOPerformance

Swap back to stock type plugs and see if the problem persists.

Steve Mack

iTrader: (5)

Are we talking about injectors or spark plugs?

upandcoming

iTrader: (20)

Change the spark plugs?????

Injectors.. I changed them out now my car wont start with the maf plugged in.. No vac leaks, no injector leaks, why would it do that now??

QuickStyle

what size injectors did you put in?

jv9999

iTrader: (1)

Put all your vacuum lines back in the right places?

upandcoming

iTrader: (20)

22lbs and I lowered the fuel pressure to 38
back where they were when I started..

jv9999

iTrader: (1)

Check all the vacuum lines again, both ends, especially the PCV, booster, and evap canister ones. They will make a big vacuum leak.

QuickStyle

i didn't know bosch made 22lb injectors anymore, unless you got them used. but i'd put your fuel pressure back up to 45psi at idle, 50-52 with vacuum disconnected, 38 is a bit low, could be causing your problems, i also second jv9999's suggestion about checking all vacuum lines, make sure they are hooked up and in the correct place.

Guest

22's are the wrong size for a 305. Even lowering the pressure isnt enough, need to run about 33-34psi. Better thing to do is get the right size, or reprogram the chip.

upandcoming

iTrader: (20)

I check again..

I got them from fic, reman.. I will try that after I check again for vac leaks.. I put all the lines back where they were..

would it work with 33-34? I do not have the equipment to burn chips yet, that was my next things to get..

QuickStyle

generally you could compensate for different injector sizes by changing the fuel pressure, but too low of a fuel pressure and it wont run right and won't have proper atomization. the correct thing to do is put the right fuel injectors in, but to get it to run correctly i would try the stock fuel pressure, after a little bit of driving the o2 sensor will be able to compensate for the larger injectors, but it can only compensate so much, and it won't compensate at all in open loop or WOT, so its going to run rich.

i suggest to get some of the ford 19lb yellow top injectors off the guy on ebay, he sells them for $100 i think, and they are cleaned and all that other good stuff. i've even been able to find some of them on ebay used for as low as $10 bucks, if your lucky. and they are a perfect match for your car, no fuel pressure adjustment or ecu tuning required.

irocuroc

i think all the yellow tops are rated at 39 psi 19.25lbs.. the yellow design 3 are the same.. at 43.5 psi they flow like 21.45 they call them 22. It is not the injector.. he changed them but something happened. I know tons of guys including me in my wifes 305 is using the yellow bosch 3... Runs great.
Are you sure the runner gaskets are not leaking underneath or something like that... With the maf unpluged it runs,, Are you sure the Maf is putting out the right signal to the ECU..

QuickStyle

all injectors are rated at the industry standard of 3bar(43.5psi) 39psi is just the rail pressure that ford uses.

TKOPerformance

Troubleshoot the MAF. If it runs without it, but not with it this seems to indicate that the ECM is not getting the right signal from the MAF. Are you getting fuel pressure when trying to start it with the MAF connected? Purge the rail of pressure and then check. If you are getting pressure then the ECM is triggering the fuel pump, if not then the MAF is telling the ECM that something is so wrong that it shouldn't trigger the pump.

If you are getting fuel pressure with the MAF connected check the injectors for firing with a noid light. If you've got fuel pressure but no firing then the MAF signal is confusing the ECM so much that it isn't telling the injectors to fire.

You aren't going to radically change the injector's flow with just fuel pressure changes on a typical AFPR. You may be able to swing the pressure 10psi. Your fuel map will be pig rich, but the car should still run. My 350 TPI ran with 30 lb/hr injectors, but the exhaust would burn your eyes. I don't think the injector size is your problem.

irocuroc

not to say you are wrong, but you are. let me explain. OE injectors are rated at the rail pressure that that manufacturer uses, The ls1 for instance uses a bosch 3 part number 0280155931 rated at 28.6lb.. but the ls1 runs at 4 bar 58psi.. if you put that injector in our cars it only flows 24. so why does gm say its a 28lber. Same thing with the c6 gm says it has a 34lb but only at 58 again. Heres a paragraph from the 2009 Ford Motorsports catalog (available to all as a downloadable ppdf. ) check out this from their injector section page 153
The purpose of going into all this detail is to convey the message that if you choose your
fuel injectors based on a pressure of 39.15 psi delta (which is the pressure at which Ford Racing specifies the flow rate), the injectors will be correctly sized
regardless of which fuel system you actually have, and also to show you that fuel pressure on ERFS vehicles can change based on a number of conditions.
only the aftermarket uses a standard of 3 bar.. understand this because self tuners are not compensating for the 4 lbs extra fp,

QuickStyle

the ls1 28lb injector is rated at 4bar. i understand that the aftermarket uses a standard of 3bar but saying that the 19lb injector is rated at 39psi is incorrect, it is rated at 3bar. rich at cruizin performance did a test on his injector machine with ford 19lb yellow tops, and they flowed 19lb @ 3bar 43.5psi. he has a post here on the boards but im too lazy to find it. i also did my own test once with the yellow tops, i had stock 19lb injectors on a 305 iroc and used my innovative wideband o2 and datalogged some afr ratios at different loads/rpm, and after swapping to the ford yellow tops i did the same test and the afrs were the same for both tests +/- 0.1 afr. this is with closed loop disabled, so after doing these tests i did not need to retune my ecu.

irocuroc

well RC says different and I guess you did not go to the Ford Racing 2009 catalog I referenced above. Heres another quote from Ford, not a fuel injector repair guy. So, read this and decide for yourself.. this is from page 152 of the 2009 ford racing catalogue.. I guess Ford is wrong also if the yellow top is a denso it is 19 if its a Bosch with the 4 holes it flows more.. I know this because RC told me I could not use the two different on the same engine
"All injector flow rates are quoted at a delta pressure of 39.15 psi. To convert to a delta pressure of 43.5 psi, multiply flow rate by 1.054.
and please I am not trying to start anything here but, I have been in the repair business all my life and learned that sometimes thing are not what I thought, if I am wrong I admit it. But to contradict Ford themselves is kind of ridiculous

Shadygrady

iTrader: (3)

Question.I`m a little confused now.I`m about to install some LS1 injecters with my TPIS manifold an slp runners.What #/hr should I have my tune done for(24#?) and what would be the optimal FP(43.5)?

irocuroc

if they are the 931 they are 28 in an ls1 24 in your car at 43.5,, there is another ls1 injector 26.6lbs.. looks the same but the last 3 of the part number is 7 somethin something.. can't remember.. but they are 22.5 in your car,,

Shadygrady

iTrader: (3)

These are the numbers on the injecters.One side says12555894.The other side says 0 280 155 890.Underneath the B on this side says 927 andnext to that on the injecter body says 970.I think he said they were 26# on his LS1.thanks again.

irocuroc

they are the 26 so they are 22.5 in our cars.. if you have afpr run them at 58 but i don't think the stock pump will work.. they are also to short you need to put a ring on the lower grove to raise the installed height

Shadygrady

iTrader: (3)

I knew about the insalled hieght issue and the extra o-ring but only 22.5 in our cars @58 psi.I`m pretty sure the stock pump will not like that pressure for long if at all.Ive tried from 42 to 50 psi FP with current injecters with no notable performance differance positive or negative.I was planning on upgrading the pump cause I want to run some nitrous eventualy but I`m pretty sure I could use about a 24#/hr injecter.Atleast thats what the guy at FIC and others have said.Thats really no better than what I`m running now.I know the bosch is amuch better injecter than my crapcells especially the pattern and atomization but I may have to buy some more.I do have some ford 24#ers but the need to be sent off to be cleaned and I could just about buy another set of bosch design III`s for about 25 bucks more and get a better injecter.Another set back.

QuickStyle

I did not see any link that you posted, but i think i've seen it before and read it, and you are right about what it says, but when you test something and it shows otherwise you really can't argue against a test like that. The machine that rich at cruizin performance was using is meant for just that, measuring injector flow rates, if an injector is advertised at lets say 50lb/hr @ 43.5psi and you put it on a bench test @ 43.5psi and it only flows lets say 20lb/hr, would you still treat that injector as a 50lb/hr injector? no, because its not what its flowing.

Guest

Call Ford and ask them. The information posted above is the same thing they told me over 10 years ago. Bosch may flow test them at 43.5, but that isnt what the Ford advertised flow rating is at. Its not what they programmed into their computers, either.

upandcoming

iTrader: (20)

could I change out the chip with a 350??

TKOPerformance

You could change to a 350 chip, and it will put your fueling table closer. A custom chip is still the best choice, preferably burned using actual wideband O2 readings taken while the car is in motion.

If the Ford catalog says that they rate their injectors at a different pressure than industry standard then I guess they do. This wouldn't be the first time Ford did something in complete contravention of convention. The bottom line is that an injectors rated flow is only going to help you match the injector to an engine. In other words, if you need 30lbs/hr of fuel to meet your HP goal then no 24 lbs/hr injector is going to work for you (at least not very long, you might be able to run it at absurd fuel pressure and a 100% duty cycle, but this will kill the injectors in short order). I could take two motors built with identical parts and put the same injectors in both and the fuel tables I would have to create based on real world feedback might be different. So, the tables you will need for two different engines are going to be very different. You need enough injector to fuel the motor at no more than a 80-85% duty cycle at reasonable fuel pressure. Everything beyond that is tuning pulsewidth based on A/F ratio and conditions. It's what people used to do with carbs by changing jets, modifying idle circuits, changing secondary springs, etc. The difference is that with EFI you can tune for the best fueling under all conditions. Carbs always make compromises. The tradeoff is the added complexity of EFI.

A real man admits when he's wrong. Arguing a position that is untenable is tantamount to insanity.

irocuroc

the link is on google just go to the 2009 Ford racing catalog and go to the pages to read the info.
The machine you are talking about flows the injector with a test fluid not fuel. also the off time of the injector is not calculated in a timed static flow test. A real test would be pulsed for 1 min at a pulse rate duplicating 80% DS then calculating the off time of that injector during the test. (off time is everytime it closes it takes time) then adding the lost flow during that down time to the numbers you get after the full min. Measure in grams per second then calculate the amount of lbs per hour that the thing flowed using a test fluid that weighs the same as fuel, approx .73 sg.

Fast355

iTrader: (2)

I happened to mess with this around 6 years ago myself. Put a set of yellow tops in a 5.0 TPI. It ran consistently about 10% richer.. Ford injectors are rated 19.25# @ 39 psi and flow 20.3 lbs/hr @ 43.5 psi. The stock regulator on this TPI was delivering 47 psi. At 47 psi the Yellow tops are flowing about 21.1 lbs/hr. That is about 10% more fuel and enough to throw a trouble code and turn the SES light on at idle. The computer could not compensate for the additional 10% in flow at idle and it sets a code 45.

FWIW- The Bosch design injectors also need changes to the injector offset vs battery voltage table.

QuickStyle

here is test data from 30lb ford injectors

Test pressure = 43.5 psi
Injector No.
1 2 3 4 5 6 7 8
60 Second Pulsed Flow Delivery (mL)
85 88 87 87 87 88 87 88
100mL Pulsed Volume
97 100 99 99 99 100 99 100
20 Second Static Flow (mL)
114 117 116 116 117 118 117 118
100mL Static Flow
97 99 98 98 99 100 99 100
Approximate pound-per-hour flow
29.25 30.02 29.76 29.76 30.02 30.28 30.02 30.28

as you can see they are flowing 30lbs/hr @43.5psi 100%duty cycle, and even though a test fluid is used rather than actual fuel, it is still .65 sg, which yes is lighter than fuel at .72 sg, but the computer calculates this into the final results that it displays at 30lb/hr. as for the real test you are refering to with 80% DC and then calculating in the off time, i don't know how that would work but seems like that way would have an even lower lb/hr rating, and i don't think thats the proper way to test flow injectors, even though thats how they work while on the vehicle, im pretty sure all injectors are tested at 100% duty cycle, what test are you seeing that shows them being tested at 80%?

irocuroc

interesting.. do you realize that on the static flow for 20 sec the injector flowed 114ml. thats 342cc per min.. using RC engineering and Bosch Racing website 342cc/mm = 32.88 lbs per hr. the formula for cc/mn to lbs/hr is cc divided by 10.4.. this is also the formula Marin and Lindertech uses.. so, not to beat a dead horse but why don't you send the injectors to them for testing.. Every 30 red top I have ever put in a TPI we set the constant at 32.. even my first tune with Alvin from PCM for less does the same.. So I guess we are all wrong, including RC eng and Ford. I think we beat this subject enough, I'm going to have a few beers.

Chevy8588

iTrader: (1)

the reason its running without the MAF plugged in is because unplugging the MAF sets the MIL and runs the engine on a base set of fuel maps get the car home mode, those injectors are spraying either too much, or not enough wuth the lower pressure, or the lower pressure is causing poor atomization, get them injectors out.

88blackgta

Without knowing what the specific gravity of the fluid that was used during flow testing, there is really no way to exactly calculate the lb/hr flow of the injectors. Bosch's website states they rate their injectors using N-Heptane which has a specific gravity of about 0.680 @ 25C depending on which source you reference. If the specific gravity of the fluid is higher than 0.680, the flow will be less and if the specific gravity is lower, the flow will be more. Temperature of the test fluid also plays a minor role in the flow but there is nothing that indicates whether it was a factor or not.

In reference to the above mentioned set of injectors, the lb/hr measurement says "approximate lb/hr flow". Since it doesn't seem to match the measured flow during the testing, this could have been a calculation to represent what the injectors would flow at a higher specific gravity and/or temperature.

In the end, I don't think anyone is definitely right or definitely wrong here. There's simply not enough information to form a definite conclusion.

Just my

Guest

How about what Ford says the flow ratings they advertise and use are based on? Thats plenty of info for most of us, there are just some that want to argue about it like Ford doesnt know what they have been programming cars for since the 80's.

88blackgta

The only problem with using Fords published data is that it has changed several times over the years. I have their SVO catalogs from 1996 to present. In the early years they didn't state what PSI the injectors were rated at. Then as recently as 2007, the catalogs state the injectors were rated at 40 psi. Currently they state 39.15 as the rated pressure. Then to add further confusion, Ford has sourced injectors from both Bosch and Denso and who knows whether they are rated the same way. It's the way they do things and it seems to change all the time.

Fast355

iTrader: (2)

This subject is like the Holley 670cfm TBI debate that has raged on for years. Even Holley advertising stated 670cfm @ 1.5 in/hg and MANY will try to claim its 670cfm @ 3.0 in/hg. VERY different. Through my own flow testing, I have found out the unit flows around 675 cfm @ 1.5 in/hg. Yet others refuse to believe this.

the blur

raise the FP back up.
many 305's run those injectors.

TKOPerformance

Raising the fuel pressure will make your problem worse, not better. You need to do one of two things. Either swap the injectors for a set of 18 lbs/hr injectors for a 305, or reprogram the PROM for a correct fuel map.

BTW, when injectors are flow tested they are always run at 100% duty cycle. I agree that this is not a real world test, since you would never do that on a vehicle, as it would cause the injectors to burn up. However, what the test is looking for is the absolute maximum volume of fuel that an injector can flow. As the end user you have got to calculate in for variables like fuel pressure, duty cycle, and aspiration. If you need 30 lbs/hr at a 100% duty cycle then you should really be running a 36 lbs/hr injector so you can run it at a lower duty cycle and have the injectors live. Or you may be able to up the fuel pressure from the rated pressure another 15-20 psi and effectively make a 34-36 lbs/hr injector, allowing you to reduce the duty cycle and still run a "30 lbs/hr" injector. Injectors are just like anything else. You have to know the right questions to ask and the formulas to make sure the system is properly sized and will last.

the blur

I have 21 lb accel injectors in my otherwise all stock 305, and it runs fine.
the BLM's are high, but you would never know by driving it.
and this is with a stock 47lb FPR.

ibmtech

iTrader: (1)

You are going to run into a whole different situation that I went through sever months ago. You will have to have a chip burned or severely modified for the TPIS manifold. Once you get the manifold on you will have to add tons of fuel to your AE or you will get a lean pop under acceration.

TKOPerformance

The bottom line is that his car runs with the MAF disconnected and won't run with it connected. I still haven't heard if he troubleshot the MAF or not. If the MAF is working properly then there is a problem with the fueling. If not then the MAF is the problem.

Now to complicate matters more, with the MAF disconnected the ECM should go into a "limp home mode", which will fatten up the fueling by about 20%. So how is the car running with the wrong sized injectors and too much pulsewidth on top of it, but not with less fuel?

It's really starting to sound like the MAF or something in the MAF circuit...

The injectors are still too big for the stock fuel map regardless of whether or not the car will run. Even if it seems fine you are wasting fuel, and therefor money. Plus leaner is meaner, so you aren't getting the full power potential of your engine. Get a chip made so it's right. Your wallet and your ego will thank you.

Shadygrady

iTrader: (3)

Yes I`m aware of that.Have A custom tune now and will have another before I do any driving around.thanks though

upandcoming

iTrader: (20)

Ok here whats going on..changed to a 350 chip now it wont run at all... before I did that I changed out the maf..did'nt work..I am just going to get a chip from tpiparts with a injector change and hope that works.. I put the 22's in there because they were supposed to be better, and all of the mods and future mods to it...Should the new chip fix my problem??

irocuroc

sounds like you got something going on there... the injectors are fine, even if they were 1 or 2 lb to big it would not make it not run.. are all the pins seated in the ecu.. check all the pinouts on the connectors.. something is not right and its probably something simple.. or you have a bad chip and or ecu.. don't keep thowing money at it,

jv9999

iTrader: (1)

What 350 chip did you put in? They are not all interchangeable. The injector change should not have caused your problems. It's likely something else that happened when you installed them.

TKOPerformance

Ditto with the MAF change. Did you troubleshoot it? You need to verify that it is working and that the wiring between it and the ECM is not damaged. Just because you swapped one in that you know works doesn't mean that the MAF is still not the culprit, just that the sensor itself is not the culprit. The circuit that it is a part of is just as important, probably more so.

Changing parts until you fix a problem isn't the same as fixing the problem. Especially when you run out of things to change and it still isn't fixed. Diagnose first, then spend money. That's what TGO is here for, so we can help each other fix our cars without going to shady mechanics who are going to rip you off, or spending hundreds of dollars on a repair that should cost $5.

Chevy8588

iTrader: (1)

has anyone considered the funny fact here that with the MAF unplugged it runs but with it plugged in it does not? that tells me that there is un-metered air coming in, check around the base of ALL your injectors, i know now the type III's well, i run them in my cadillac, i am willing to lay money that you lost a few pintle caps and o-rings while putting them in, or your set didnt come with pintle caps, you slapped o-rings on em not knowing they require caps. and put em in and it sucked your o-rings into the manifold. check that man, it will cause a HUGE vacuum leak and may not run :P my speed density MFI 4.9 almost didnt want to run when i lost a cap and o ring into te manifold, a MAF system will probably play hell.

upandcoming

iTrader: (20)

well it was the chip..I put the stock chip back in it and cleared the ecm and It started. so what should I set the fuel pressure at? 43?

irocuroc

glad you fixed it run the pressure at 40 with the vac hose on.

airtime

glad you got your problem fixed. i have a question about your yellow top injectors. i just bought some off ebay and i'm having trouble getting them installed. i read in previous post above about double oring or shaving the manifold. the yellow top injectors are about 1/8 inch shorter than my 305 injectors (part number 028015027). we took the shim under neath the injector o-ring from the old injectors and installed them on the new injectors to try and get them to work. i did not have time to try this an see if it will work today. is this a common thing with these four hole injectors off ebay?