ForceFedPerformance

Can NoGo or Chris B please post what they have found to be a good injector offset for these injectors. I have been playing around with didfferent multipiers based on the the Kpa range, it seems to be working better than multiping the whole table by the same percentge. Is this how you guys are doing it or are you multiping the whole table by the same percentage. Please post some multipliers.

NoGo

iTrader: (2)

I don't have my laptop on my right now, but I will try and get it tomorrow.

The curve, from my experimenting, shifts down and forms more of an L shape. The offset curve for the different injectors seems to stay largely the same in the right 2/3'ds but shifts significantly in the front 1/3 depending on the injector.

Again, I will try to find the time (working at a site right now) tomorrow to post up some multiplications.

MIGHTYMOUSE

iTrader: (59)

i never did this with my 42's but what did you guys find was the gain from doing all this work on the offset table? mileage, starting, idling, cold start? i just never ran into anything that made me put effort into the offset table with these injectors. thanks

Phil99vette

iTrader: (11)

I just installed Ford #42 injectors. I multiplied the IFR table by 168% and started right up. MY LTFT are -1 - (-2).
Phillip

Blackbird

no-go if you have any wisdom for my regarding lucas 42's I am all ears.

thanks!

Ryan23silverado

iTrader: (1)

I'm in the same boat as Blackbird. I have Delphi/Lucas '009' 42lb injectors. Would the offset calculations be any different for a truck PCM this tuning would be done for?

Thanks NoGo.

PS I have read many of your other tuning posts to get my airflow decay stuff nailed. They were very helpfull

Nickn20

im picking up some SVO 42s, id love to hear about some injector offsets.

horist

i've got SVO 42s in my car, multiplied IFR by 162% and it's just slightly negative LTrims... but car idles for $hit and hunts alot (when I slow down, it'll sometimes hold steady idle, but other times it'll hunt up and down and finally go down so low it dies)... so any additional info on tuning 42s would be appreciated

NoGo

iTrader: (2)

Sorry for the hold-up, been busy with my *other* tuning job lately...... gas turbines.

Okay here are the multiplication factors. I did my best to determine these through the use of LTerms, air flow, and engine load. All of my work was done on a 2000 Trans Am with SVO 30#'s. Granted they aren't 42's but the curves should be quite similar.

I generated this curve to help with the large LTerm swing induced by SVO injectors when getting on and off the throttle.

The below vales are the stock columns divided by the SVO values.

DON'T PLUG THESE VALUES DIRECTLY INTO EDIT.

1 , 1 , 2.55, 1.32, 1.26, 1.12, 1.07, .99, .97, .94, .91, .86, .84, .80, .85, .88, .94, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

Use the above division values to see what the newer table looks like (do it in excel or something).

Good Luck

XLR8NSS

iTrader: (4)

Wow, I don't understand why some people have problems with these and others don't. They idled and ran great in my car and truck.

Mike00FRC

iTrader: (1)

I have the SVO 42#s and everything seems to run fine. But when looking at the data, after driving around for about 10-15 minutes, under all part throttle conditions,no WOT, I had the following ranges in sterms/lterms:

IFR scaled 168%
Avg. ~ Area(Lterms)
-.81 ~ Idle Cells 17 to 20
-5.3 ~ Part Throttle Cells 6-14
+6.1 ~ Decel Cells 0 to 5, 21
+1.8 ~ Overall average all non-WOT cells

Min. ~ Max. ~ Parameter
-10.2 ~ 18.8 ~ LTerms
-34.4 ~ 23.4 ~ Sterms
-6.30 ~ 18.8 ~ Decel
-10.2 ~ 17.2 ~ Part Throttle
-1.60 ~ -.80 ~ Idle

I am getting some part throttle knock, under non-WOT higher load and appears to be when the pcm transitions from cell to cell in the higher ranges... 11-15. Other than that everything appears to run pretty good, other than an occasional slight stumbling/bucking under very light throttle, or using the engine to slow the vehicle.

So, for the most part the stock offset seems to work pretty good, for normal drivability but I think it can use improvements to make the car more streetable at part throttle. But then again, my running FI may exaggerate any potential problems with running the stock offsets.

I'll give them a shot. Hopefully it will bring my numbers a little closer inline.

red ws6 99

Here are what the LT1 guys are using for there injector offsets. I have the msd 50 lb injectors and these numbers work great. I know these are only partial tables, but if you use Chrisb spreadsheet and a little work you can get these in. I really did not worry about the whole table because if my voltage gets down to low or too high, the cars not going to run any way.

The lucas 42 lb injector numbers appear to be wrong, but maybe the lucas are that fast. That could explain why everyone says the lucas injectors are very non linear.

Gary


Ford SVO 42# (Bosch)
12.4 12.8 13.2 13.6 14
0.62 0.59 0.56 0.56 0.52

GM 24#
12 12.4 12.8 13.2 13.6 14
0.52 0.46 0.39 0.36 0.33 0.29

Lucas 42#
12 12.4 12.8 13.2 13.6 14
0.13 0.10 0.07 0.07 0.07 0.07

LJ's MSD 50#
13.6 14 14.4
0.82 0.79 0.75

Ford SVO 30#
12.4 12.8 13.2 13.6 14
0.59 0.56 0.52 0.52 0.49

muncie21

iTrader: (14)

Doing some searching on injector offsets and ran across this old thread. What table is referenced in red ws6 99's post regarding offsets vs. various injectors?

I'm using HPT, and the only offset table I see is Offset vs KPA vs Volts.

Haans249

iTrader: (24)

Horist, your idle problems are not because of the injectors if you have inputed the proper IFR's. This sounds like its related to the Throttle Follower table. What I would recommend is changing all of your throttle follower mulitplier to 1, and then adjust your throttle follower airflow table until you can get it nailed down. If your Throttle follower airflow doesn't decay fast enough (before you reach your desired idle speed) then it will cause the problems you are describing. Just start by reducing the lower tps values and log, then reduce more if need be. You want the timing (decay to zero RIGHT when you reach desired idle) to be as dead on as possible for all TPS values.

Good Luck and let us know how it goes,
Adrian

TAQuickness

iTrader: (28)

Adrian - Take a look at the original post date.

AzzHauler

iTrader: (3)

Why is half of this thread talking about the IFR table and the other half talking a the offset table? As far as the offset table, I had to play with it waaay back when I got my svo42's, at idle if I recall correctly it was rich enough to smell gas in the exhaust and something about my ltrims hanging like 15-20% off of where they would be for driving, and may have been messign with idle speed. I got a table from GeorgeC I believe and that fixed the idle ime but the rest wasn't right. Think I ended up blending them, and never got a chance to mess with it again.

IFR scaling is a whole 'nother story. (Mine is completely whack for 42's...)