WS6FirebirdTA00

iTrader: (33)

set the pe map enable to 75-80 kpa, try and get some numbers in that range and it will let you know how its off. i would set the pe up how you want it and start to get the ve in line. thats about the best you can do withotu a WB, which i hope to get one soon. what did you get lm-1?

WS6FirebirdTA00

iTrader: (33)

the a/f gauge wont tell **** really. like i said before., what is the wot reading on the o2s?

ZL1Killa

iTrader: (17)

don't know about the O2's....I will make a separate log on that tomorrow....make that first on my list...shoulda had that logging. Yeh I got the lm-1 from Dynotune.org--pm Dean and he will get you one...

hey mike, how did you tune yours?? did you go Speed density??

WS6FirebirdTA00

iTrader: (33)

yeah SD, i wanna get a WB and check it out soon and see how close i did without the wideband. only time i went to the track it ran rich as ****, i had to be in the 10:1 range, o2s were reading about 980 mv, i run right at about 890 lol. ill work on my parents for a WB for christmas, well part of one at least lol, gettin older so no more presents plus my money has to build up, heads and cam will take it out of you lol

ZL1Killa

iTrader: (17)

lol. Oh, my AFR gauge is tied into my O2 sensor so it will correlate with what the O2 voltage is outputting. It is saying that I'm rich.

Can you have a higher number than 100 in the VE table for Natural aspiration motors??

Also if i took away fuel from the PE table around 5k and on up...then should I put that fuel back and take away from the VE table at those values?? And if I'm going rich then why are the LTFT's going crazy positive like up to +20?? The best I can at least say is I'm going to wait to get the wideband....this is too much....lol. At least I got rid of the knock retard. I might play with this a little more and see what happens. TAQUICKNESS...I can't be running lean, there is no way..its gotta be rich.

But anywho..I'll play with it here for the next couple of days now that I got some knowledge on how to rid myself of KR.

ZL1Killa

iTrader: (17)

I think that I should decrease all the values in the VE table by a good percentage and see what happens

WS6FirebirdTA00

iTrader: (33)

decreasing it will lean it out. before you do that make sure the o2 voltage is no lower than about 890 or so, 900. if its in the 930-940 range or above you can lean it out some.

WS6snake-eater

Guys unless he is running SD...messing w/ the VE over 4000 rpm will not do ****. He is in pure steady state MAF mode by then.

Also, it sounds to me, judging by your 1st post that you are having some kind of pump/injector problem...If you are running stock 28lbs injectors and the stock pump there is absolutely no reason to mess with the IFR table. You need to set the IFR table back to stock and start all over. Figure out why your not seeing the correct PSI, and solve that MECHANICAL issue before you move on to tuning.

ZL1Killa

iTrader: (17)

?? what correct PSI?? idling we are seeing 58psi according to the gauge and 60 according to a calibrated gauge. At WOT I have seen both gauges drop down to about 56 or 58psi.


NOW wait a minute....get your stock injector table out. take a look at it and compare it to this attached excel sheet at 43.5psi and 28.8# injectors. Is that formula wrong?? fuel pressure and injector size play in part with how much the injectors inject per second into the cylinder

Then SINCE I"M SEEING 56PSI, I will adjust the actual fuel pressure to 56PSI AND THEN LOOK AT THE NUMBERS.

The first reason at all that I messed with the IFR table was because it did make a difference and several other people had changed it because they were noticing higher than 43.5psi in their fuel pressure. BUT THE POINT is that I"m running too rich......thats how i got rid of the knock retard....this ain't about the damn injector flow rate table. I KNOW MY INJECTOR FLOW TABLE IS RIGHT. BECAUSE if it is wrong then everyone else's is too. they all have used this excel sheet.

ZL1Killa

iTrader: (17)

do you know what your ACTUAL FUEL PRESSURE IS?? I would like to know. is your car an auto ir 6 spd??

WS6snake-eater

My pressure in both of my Ls1's one auto one a six speed is 58 PSI...this is the correct pressure. Yes the pressure will fluctuate slightly plus or minus 1-2 psi depending on conditons will driving...ie throttle tip-in, however that is a normal occurance. With stock injectors stock pump, and a stock IFR table you should be seeing approx the same as me. If not, then I would say that you are having some sort of mechanical problem in the fuel system. There should never be a need to adjust the IFR table if the fuel system has never been touched. Now perhaps I missed something and you have modified your fuel system in some way.

WS6snake-eater

BTW that sheet you posted is for people who have changed their injectors. Yes the sheet is a correct guide for getting your IFR table correct after an injector swap. Also FWIW, the pressures you are seeing now with your altered IFR table are right in line with what you should be seeing with a stock table...This tells me that something is off in your fuel system. How many miles are on the car...When was the last time you changed your fuel filter.

ZL1Killa

iTrader: (17)

17.5k miles. So you are saying even though the stock IFR table is rated for the 28# and 43.5psi that I shouldn't have changed it even though my actual pressure is 56-58psi??

WS6snake-eater

Correct! set it back to stock and start over. You are overthinking things here. BTW when you set your IFR back to stock...make sure that you set your VE and MAF, and PE tables back as well if they have been changed...Basically you need to start over from square one.

ZL1Killa

iTrader: (17)

why? why do i need to change the IFR table?? it doesn't make sense. If the injectors aren't at 43.5psi then why set them at that??

the actual fuel pressure is 56-58psi, why do i not need to change anything for this??

WS6FirebirdTA00

iTrader: (33)

put your ifr table back to stock. i thought you were still in the process of an sd tune which is why i said to mess with the VE? are you not in sd anymore? or have you ever been? if not you need to. like i ahve been saying, no need to do any settings for 43.5 psi its wrong. if this is starting to confuse you pm me and ill elaborate. you CAN change it for 56 at wot, just make sure you get data for all points so you can had a nice cruve. makes the ve table look a lot better as well when you get this right, no odd fueling changes

WS6snake-eater

You are confusing injector psi with rail psi...They are two totally different things. If your Rail PSI is 58ish then you are good to go. I wish I knew how to explain it, but I suck when it comes to explaining things. Do a search in the Fuel Section. I'm sure there is someone more qualified to answer the question in a more technical way then I can. My answer is "That's the way GM set it up." Why I don't know, I've just come to accept it.

Oh well let me take a shot at explaining it anyways... when we say that an injector is rated at 28 lbs @ 43.5psi; we are using the 43.5 psi as a constant. It's kinda like saying that cylinder head "A" flows 305 at .600 lift @ X inches of water. We have come to accpet X as the constant used on most flow benches as to get an accurate comparsion between heads. Just as 43.5 is GM's constant when comparing one set of GM injectors to another. Ford on the other hand uses a different contant when flowing/comparing their injectors.

In other words 43.5 psi is just technical jargon used to confuse you. The number is really no important until you want to start using different injectors across different platforms or manufactures that happen to use a different constant to measure flow.

I hope I didn't just confuse you more.

WS6snake-eater

Damn I think I just confused myself...LOL...

Seriously though set everything back to stock and start over. Make sure you put your ve, and pe back to stock too, as all of the info that you have entered into them to date has been scewed due to the incorrect IFR.

WS6FirebirdTA00

iTrader: (33)

stock gm injectors are rated at 58 psi, or 4 bar (i am 99.9% sure of this becuase i had the same question before so unless i was given wrong info then they are 58 psi, and that is because that is the pressure of the fuel system)

let me get this strait. when you put the injectors in there you said they flowed at 43.5 right? and rail pressure of 58? thats why you are running lean and getting knock if thats the case. you are telling the car the injectors are larger than they really are, giving a shorter pulse width, not enough fuel, making it lean and knock. put the table back to stock and relog. like snake-eater said, you have to disable the maf and run sd to tune the ve table, or else it does nothing. i dont know if you are sd still or not. though

ZL1Killa

iTrader: (17)

ok that clears some things up....I never went SD because I don't have my wideband yet.

so my ifr table should look like this
3.628800
3.658923
3.688801
3.718438
3.747841
3.777015
3.805965
3.834697
3.863215
3.891524
3.919629
3.947534
3.975243
4.002760
4.030089
4.057234
4.084198