Scaling Injectors?

[vetteboy2k]

Heres the issue, I had a tuner send to me injectors, I ordered 42lbers. I scaled my Injector Flow Rate {B4001} accordingly however at idle I was maxed +25 LTFT with the following

LABELS Injector Flow Rate (Lbs/Hour)
Manifold Vacuum inHg Value
0.0 42.659334
1.5 42.969358
3.0 43.279383
4.4 43.465397
5.9 43.775421
7.4 44.085446
8.9 44.271460
10.3 44.581484
11.8 44.767499
13.3 45.077523
14.8 45.263538
16.2 45.573562
17.7 45.759576
19.2 46.069601
20.7 46.255615
22.1 46.565639
23.6 46.751654

Too get the LTFT at idle in check I scaled them back to the following.

LABELS Injector Flow Rate (Lbs/Hour)
Manifold Vacuum inHg Value
0.0 32.614549
1.5 32.862568
3.0 33.110588
4.4 33.234597
5.9 33.482617
7.4 33.730636
8.9 33.854646
10.3 34.102665
11.8 34.226675
13.3 34.474694
14.8 34.598704
16.2 34.846723
17.7 35.032738
19.2 35.218753
20.7 35.404767
22.1 35.652786
23.6 35.776796

I am just not certain what injectors they sent me, and they can't remember anymore what they shipped. I looked at a bunch of tunes from HP Repository and it looks like all 42lb injectors are in the 44-49INHG

Is there anyway to tell what injectors I have? Whats the proper way to scale IFR {B4001} if you don't know what flow rate they are? By LTFT's at idle? Any help or links are appreciated.

[mistermike]

Is it possible that your fuel pressure is higher than the pressure specified for the injectors?

[vetteboy2k]

That is definitely a possibility, but I don't know that for 100% certain.

What is the best way to go for scaling the injector flow rate?

Do what I did and just scale them till ltft's are 0 to -1 at idle?

Just say my fuel pressure is higher than the injectors were tested at, it made my scale lower, shouldn't it make it higher?

[redhardsupra]

you dont scale them, you calculate them. go to pcm section on ls1tech and in the stickies there's a spreadsheet that will give it to you right. i've done over a dozen of cars with it, and it works perfect.

[vetteboy2k]

RedHardSupra,

That is how I came up with my original figures in the first table. I used the excel table that was modified by you. Attached are some pictures that I found of the injectors and a sheet that came with them. I have a Corvette C5 2000.

http://www.easiwebsites.com/injectors/DSC00145.gif

http://www.easiwebsites.com/injectors/DSC00148.gif

http://www.easiwebsites.com/injectors/DSC00149.gif

http://www.easiwebsites.com/injectors/DSC00150.gif

[SSpdDmon]

Well, you just posted the problem. Those injectors are flowed at 43.5psi and I believe LS1's run 58psi (4bar). See http://www.ls1tech.com/forums/showthread.php?t=326601 for more info.

[John Skiba]

vetteboy2k - Email me your tune w/ a complete list of mods and I'll setup tables over the weekend for you. It's not just one injector table that you need to modify.

[vetteboy2k]

Email Sent. Thanks.

[vetteboy2k]

Doing some more research, I found the part number of my injector.

Part # 01D030B

It's a Lucas based fuel Injector flowing 440cc@3Bar. Using a Calculator for cc->lbs
440cc=41.904761904761905lb's

Then calculating flow rate @43.5psi -> 58psi
41.904761904761905=48.387451132082916

So basically I have 48lb injectors.

What doen't make sense to me is that the figures I entered into {B4001} were for 42lbs, and it was showing an extremely lean condition at Idle (pegged at +25 LTFT's). I can recalculate my injector numbers, but what other table do I need to change so that everything is scaled accordingly?

[vetteboy2k]

Recal {B4001} my table looks like the following

LABELS Injector Flow Rate (Grams/Second)
Manifold Vacuum kPa Value
0 6.096126
5 6.134119
10 6.171878
15 6.209407
20 6.246711
25 6.283794
30 6.320659
35 6.357310
40 6.393751
45 6.429986
50 6.466017
55 6.501849
60 6.537484
65 6.572927
70 6.608179
75 6.643244
80 6.678125

I will post back later today what my ltft's look like at idle this time around.

[vetteboy2k]

Well Idle LTFT's were again pegged at +25 with the new recalibrated table. Don't know where I went wrong. As John has stated I need to modify more than one table for the injectors, but I have searched and come up with no mention of other tables to change when swapping injectors.

Any advice?

[GMPX]

Yeah, what other tables were they?.

Cheers,
Ross

[vetteboy2k]

Didn't change any other tables just the IFR Table. I sent my tunes to John in email, but haven't heard back from him. Being I was at the shop yesterday wiring up the LC1 figured I'd give it a try with just the IFR table calculated the right way b/c now I know what injectors I have.

What other tables do I need to modify, then I am sure I can get this all dialed in ready for Auto-Tuning and the Track!

[redhardsupra]

send your bin to marcinpohl at gmail dot com and I'll fix it up.

[vetteboy2k]

E-mail sent :!: Thanks man :!:

[vetteboy2k]

Well according to redhardsupra the IFR Rates I had and posted above after finding out what injectors I had were right.

Why is it then are my idle trims pegged at +25LTFT? What other tables need to be changed?

[foff667]

Well according to redhardsupra the IFR Rates I had and posted above after finding out what injectors I had were right.

Why is it then are my idle trims pegged at +25LTFT? What other tables need to be changed?

not according to the spreadsheet listed on his site http://www.transamws6.net/HPTuners/injectors.xls check it out for yourself. keep in mind according to your paperwork your "42lb injectors" were rated at 42.5psi...so plug in what they were rated at, your fp should be 58 and the rated lb which is for 42 and your looking at 48.xx, 49.xx, etc...youve had to plug in #'s for 30lb injectors to get your trims in line...either your car has non tuning related problems or you didnt get the injectors you paid for.

[redhardsupra]

why don't you retune your VE table so it would fall inline with the new injectors?

if IFR was tweaked/bullshit before, and then you dialed in your VE on that, now if you put in your IFR to right settings, you're gonna be off on VE.
HOWEVER, if your IFR was right before (let's say stock) and you had your VE dialed in, and then swap in bigger injectors and proper IFR config, your trims should be about the same.

I did that experiment just before i swapped in bigger injectors, and after adjusting IFR, trims stayed dead on, just like before.
that's the 'sideeffect' of not lying to your computer ;)

[vetteboy2k]

Well IFR Table is exact when comparing to the excel file made by RedHardSupra (thanks man), Checked the tables in the PCM, exactly as the excel file shows. I confirmed the injector part # tonight 01D030B. Its a delphi injector as shown here http://66.70.180.37/621031.html and it says exactly as I calculated before 48.38lbs at 58psi.

Car tonight was the same +25 ltft's. Left the fule pressure gauage at a friends house so I will confirm tomorrow the exact fuel pressure at the rails.

As far as the VE table it is still stock. I have never tuned the car yet and tonight I loaded back in my 2000 Stock program, just changing the Map for the 2bar sensor, and the IFR table and again +25. Ahh I am going crazy. Tomorrow if the fuel pressure at the rails is 58, I will be at a loss.

So basically I did get the injectors I paid for and its looking more like a non tuning related problem. I will post tomorrow what the fuel pressure is, I am actually hoping the pressure is low so then I can just track down that problem and be on my way to actually tuning the car.

[Dirk Diggler]

if you are trying to tune for the mods in your sig and are tuning in SD mode then you stock ve table wont work at ALL!!!!!!. YOu are gonna need to get a Wideband and get the ve table dialed in. With as much money as you ahve in your setup you should spend a few extra dollars and get a WB

[vetteboy2k]

I have a LC-1 Wideband thats in the process of being installed, slight issue with the heater ground showing a short. I have a good chassis ground have tried 2 other grounds and have tried a different O2 sensor and a 2nd LC-1 unit, still all showing the same 1flash error. I have spoke with Innovate about it and we are trying to fix it.

So far I am not trying to Tune SD. MY car is still on the lift a foot off the ground. I am not going to be trying to dial in the VE with a wideband until I figure out why idle trims are so far off when I have the correct IFR settings for the Injectors I confirmed that I have.

I will be out at the shop shortly with my fuel pressure guage to confirm fuel pressure at the rails.

[vetteboy2k]

OK LC-1 Wideband is squared away, no more issues with that...however tested fuel pressure at the rail and I am getting 61.5psi. I do have a racetronix boost-a-pump installed so thats why its probally higher than 58.

Now I have the IFR table set for the injectors at 58psi, I know I can recalculate them for the 61.5psi, though don't think that will do any good b/c it will just make me leaner than I already am. Is that true?

What could be the cause of the LTFT's being so lean? Pegged at +25!!!

[joecar]

Some possibilities:
Air leak before O2S.
Air leak after MAF.
MAF incorrect.
VE incorrect.
IFR incorrect.

[joecar]

Log the injector pulse widths and duty cycles and see if the injectors are being pegged;
if they are, then they're not flowing properly or they're smaller than your previous ones.

[vetteboy2k]

Ok, well tonight I was back at the shop again after work. I finished the Wideband O2 install, put the dash back together some, hooked up the WBO2 to flashscan and saved a log. I logged injector pulse width and Injector duty cycle as JoeCar said above, but i also logged the wideband AFR, commanded AFR and some other things. If someone can look at it the file is here http://www.easiwebsites.com/efilive/Log_High_Ltft_0000.efi and see if anything pops out at anyone of you.

Side note heres some pics of my install
Fuel Pressure at 61.5
http://www.easiwebsites.com/efilive/pics/DSC00197.gif
Flashscan LC-1 Hookup
http://www.easiwebsites.com/efilive/pics/DSC00198.gif
Dash Boost Guage A/C Lights on
http://www.easiwebsites.com/efilive/pics/DSC00199.gif
Dash Boost Guage A/C Lights off
http://www.easiwebsites.com/efilive/pics/DSC00200.gif
Dash Manual Boost Controller and Boost Guage
http://www.easiwebsites.com/efilive/pics/DSC00201.gif
Dash Manual Boost Controller and Boost Guage More light
http://www.easiwebsites.com/efilive/pics/DSC00202.gif

[WicketMike]

i used redhardsupras excel file for the 42#'s. i used 42lbs @ 43.5psi and put it into the IFR table, is there any other injector tables i need to fix now that i have these 42lbs?

thanks

[WicketMike]

what about injector offset table?