Confused on IFR settings

[samh_08]

Hey guys,
I have a heads/cam 2005 LQ4 swapped into my 86 monte carlo and I just got some bigger injectors. I got the new LS2 style injectors from Fuel Injector Connection (great guys to deal with) and now I have some tuning questions.

First of all, I have a returnless fuel rail with a Corvette fuel filter/regulator giving me ~58psi. These injectors are flow matched at 42lbs/hr @ 58psi. My main concern is what value I am supposed to put in table B4001 (IFR.) A constant rate or a slope that rises with vaccum?

When I called Fuel Injector Connection, they told me to put in the injector tables from a 2006 GTO and calculate IFR for the bigger injectors. Only problem with that is the tables are different from my PCM to the GTO's....

I posted my current calibration that I have for these injectors. One other thing I would like you to look at is my VE table..I am currently doing AutoVE and my values look pretty high compared to other tunes and I would like to know whats going on.

Let me know your thoughts, Thanks :cheers:

[hquick]

Copy all of the injector tables from the 06 GTO as suggested by FIC.
Change the IFR table B4001 to your recalculated IFR's.
They should be:
5.292000
5.324981
5.357760
5.390339
5.422722
5.454913
5.486915
5.518732
5.550366
5.581821
5.613100
5.644205
5.675140
5.705907
5.736509
5.766949
5.797229

Those numbers are 42lb/hr injectors rated at 58psi running a fuel pressure of 58psi.

[samh_08]

I came up with very similar values with the IFR spreadsheet. Are the numbers you posted from somewhere else (I heard you bought the same exact injectors from them.)

Care to share your tune with me? :secret:

[hquick]

No secrets here...this tune is a product of the EFILive forum and its many teachers :cheers:
Keep in mind...mine is a 5.7L supercharged L31 truck motor. Mine are 44lb/hr at 58psi.

[samh_08]

Thanks for posting it. ;)

Couple of things I noticed and have questions about:
1) {B4006} Small Pulse Threshold is 4 from a 06 GTO and yours is 3.996945. Is there a reason for this?
2) {B3701} IPW Voltage adjustment varies from all 3 tunes I am comparing. Did you do anything with this table, and why?
3) {B3704} Injection bank assignments: Your values are different from most tunes I've seen...any reason?
4) {B4003}, {B4004}, {B4005} All differ from the 06 GTO tune..Again, any reasoning?

Let me know you thoughts and thanks for the help,
Sam

[hquick]

From memory I used a 2002 Camaro settings.
4 and 3.996945 are the same thing as far as the PCM is concerned.
Don't think I changed B3701...but I may have. It effects decel fueling, ie..rich or lean on decel.
B3704 is strange...seems to only be like that for the L31 truck motor.
03,04,05.....I'd just try them as in the 06 tune suggested by FIC.
Yours is an 05...and they're the same injectors as in the 06....give it a try.
There's alot of 'black magic'(and nonsense..so it seems) out there as far as injectors and tuning them goes...and seems to be no 'deffinates'.
If your injectors are flow matched (and they are), and you have the correct rating (which you do)...that's a good start.
To answer one of your original questions, sloping IFR for returnless fuel system. Flat line (same value in all columns) IFR for return system.

[samh_08]

Sounds good. I assume a 2006 GTO has the same regulator as I am using?

That is probably the main question I have right now, followed by B3701.

Let me know, Thanks again.

[hquick]

Don't know about the reg. If it uses 58 psi as standard fuel pressure...then it'll be fine.
Just take it easy and look for 'sane' values in logs. Follow the autoVE process.
Your B3605 looks a little strange with that big cut out in it...but I'm not really familiar with the newer vehicles.
Are you running OLSD at the moment?

[samh_08]

Yes I am running OLSD right now doing AutoVE which is why B3605 looks weird.

I was looking at older camaro and trans am tunes and they have the same slope in their IFR table as me. Mine cant be right being they have a return style fuel rail and I do not. Shouldn't I have one value across the board?

Any thoughts on if I should try to convert the injector timing tables over from the GTO? The table dont exactly match up but could still be important to have right.

I attached a screenshot of what Im talking about.

[hquick]

Both those tables use different values.
I'm not familiar enough with the newer tunes/PCM's.
Hopefully someone else can chime in.
I'm a little rushed right now....heading to work. I'll try to take a look at lunch time if nobody else has helped out by then.
Personally....I'd just try swapping the tables which use the same axis'.

[hquick]

I'd be using this as a B3605 table for the AutoVE

[joecar]

Sam, the 1998+ Camaro/Firebird had returnless systems as did the 1999+ Corvette.

[samh_08]

Makes sense now, thanks Joe.

I just put in the Injector Voltage offset along with the minimum pulse and small pulse adder from a 06 GTO in my calibration and now it idles rich as hell (its raining and I havent had it on the road). Should I keep these values as a known good and adjust my other tables accordingly?

Other things I noticed:
1) A 05 Vette LS2 and 06 GTO LS2 both have the same injectors, why are some of the tables different?
2) My stock Injector Voltage offset table is quite a bit different from any other calibration. Is this table changed with each different injector, or is it used to tune something else?

[hquick]

As I said before...really hard to find decent info on injector tuning. Apparently Greg Banish has a DVD or book coming out on this exact subject.
Main thing is you have the IFR correct...and you can play with the others.
I think you'll find alot of variation throughout the rest of the settings depending on the vehicle they're used in.
For me...I've found there's so much conflicting info out there...it's a matter of trial and error....baby steps.
Use some 'known' OEM settings and see how you go with the AutoVE process.
Did you see the difference in the B3605 table I posted?
I think you would have been seeing alot of 'semi closed' loop with the settings you had...which would be throwing your AutoVE right out.
Don't forget to reset your fuel trims now.

[5.7ute]

Not knowing too much about the US cars I can offer a couple of generalisations.
If the 06 GTO which your injectors came from run the same returnless system, you should start with all of their injector tables.
However if one was returnless & the other was a manifold referenced return system the offsets would be different due to the different pressure differential over the injector.(this will change the opening/closing time of the injector)

[samh_08]

I just drove it :shock:

Not good...Haha AFRs all over the place. Are the injector voltage offset tables made for the injector itself or exclusive to each vehicle's tune?

I know Im not making myself very clear but its hard to explain. Is the table for the injectors charactoristics or tuned to supplement other tables in the calibration?

Let me know if you follow me, Thanks :hihi:

[5.7ute]

I just drove it :shock:

Not good...Haha AFRs all over the place. Are the injector voltage offset tables made for the injector itself or exclusive to each vehicle's tune?

I know Im not making myself very clear but its hard to explain. Is the table for the injectors charactoristics or tuned to supplement other tables in the calibration?

Let me know if you follow me, Thanks :hihi:

The offsets & all the other injector tables are based on the injectors characteristics, not the rest of the tune.
FI offset is pulsewidth added to the injectors calculated pulsewidth to allow for the injectors opening/closing time.
Small pulse adjust is added or subtracted pulsewidth to give a linear injector flow rate. etc,etc

[samh_08]

The offsets & all the other injector tables are based on the injectors characteristics, not the rest of the tune.
FI offset is pulsewidth added to the injectors calculated pulsewidth to allow for the injectors opening/closing time.
Small pulse adjust is added or subtracted pulsewidth to give a linear injector flow rate. etc,etc
Thanks for the explanation. So if I have LS2 injectors, which tables do I use? The 'LS2 injectors' somehow have different characteristics in two vehicles that have them, 05 Corvette LS2 and 06 GTO..I have been comparing with stock tunes from holdencrazy.com.

If anyone has time, I would appreciate if you would take a look and see what I am talking about.

Let me know, Thanks again!

[5.7ute]

I see what you mean. Both the offset & small pulse adjust are different in each tune. Whether this is due to a change in the injectors internals or an incorrect previous calibration I dont know.

[hquick]

Personally....I'd just pick one and start on the AutoVE.
This is the whole issue with setting up injectors. There's so many variables...even for vehicles using the same injectors.
What's the motor out of?

[5.7ute]

Having a bit of a think on this, I believe you will be able to determine which injector tables suit your injectors. Since you know that the IFR on your injectors are correct any discrepency in actual/commanded afr can be attributed to an incorrect offset.
First dial in your VE table with the injector tables from the 05 or 06 tune. Then richen the commanded AFR at least a full point(eg14.5 to 13.5) & see what the actual AFR is. If the offsets are correct you should track commanded as accurately as before. If not then your offset tables are incorrect. Remember to log your injectors pulsewidth & filter out any data under 4.00ms. This will remove any influence from the small pulse adder table.

[samh_08]

Very nice ;). I like your thinking. Wouldn't I want to leave the small pulse adder in because that is also a variable? Did you happen to compare all of the injector table differences, or just the voltage offsets? The small pulse adjust tables are different between the Vette and GTO as well...:doh2:

Im guessing I cant really do anything about the Injection Timing trim tables because they arent in the same units?

Thanks guys.

[5.7ute]

Very nice ;). I like your thinking. Wouldn't I want to leave the small pulse adder in because that is also a variable? Did you happen to compare all of the injector table differences, or just the voltage offsets? The small pulse adjust tables are different between the Vette and GTO as well...:doh2:

Im guessing I cant really do anything about the Injection Timing trim tables because they arent in the same units?

Thanks guys.

Adding in more variables will just make it harder to get right as you will not know which table is incorrect. I would also keep the small pulse adjust tables & offsets as a pair. As far as we know they could be just two different engineers version of the same injector & could give similar results.

[samh_08]

Sounds good I'll give that a shot. I'll let you know how it goes..

[eficalibrator]

As I said before...really hard to find decent info on injector tuning. Apparently Greg Banish has a DVD or book coming out on this exact subject.

Yes, the DVD is pretty much done now and I have a Demo Video Here (http://www.buckshaw.com/greg/CSI_BGM.wmv). Don't get scared off by all the HP talk, I included notes at the end of each section to show what the corresponding tables look like in EFIlive as well. Production versions (in much higher resolution) will be available shortly.

[samh_08]

Video looks like it could be a big success..Good job!

Anyways, I know you made a DVD for a reason, but would you mind enlightening us a little bit about the black arts of injector characteristics? :secret: