2002 S10 Mild 4.8/4L60 First Start - New Tuner seeking advice

[dtrev]

I have been building this truck over the last 2 years and finally at the point mechanically and functionally the truck is ready for a test drive but am still reading and learning about tuning, and will be undertaking the entire process myself and with the help of the HPTuners community. I have both of Greg Banish's books, only focused on reading through the first one (SA161) while I practically learn simultaneously. Anywho on to the truck......

2002 S-10 Ext. Cab - (Originally 2.2L/4L60E)

2004 LR4 4.8L/4L60E from 2004 Tahoe - CPW Wiring Harness
Rotating assembly was balanced at time of all block machine work
Bored .020" over to match Summit Racing Forged Pistons
Stock Gen 3 Rods
Stock Gen 3 Crank
862 castings hot tanked/valve job
Trunion upgrade
LS7 lifters
GM 12613412 Injectors (actual OEM)
Stock ACDelco Fuel Pump w/ Corvette fuel filter
Stock truck intake/throttle body
Brian Tooley Stg 2 Cam - Part number 31218132R1
212/218 duration @ .050
.553"/.553" lift
Intake centerline 111
Exhaust centerline 115
Lobe separation angle 113
EVO @ .050 - 44 BBDC
EVC @ .050 - (-6) ATDC
IVO @ .050 - (-5) BTDC
IVC @ .050 - 37 ABDC


Ok sorry if there is unnecessary info I provided, but thought I would put as much as I could there to minimize responses requesting info I already have handy. I am not sure what info to provide about the files I am attaching other than it is just the truck idling in my garage and the config I used is just the vehicle defaults that I selected from the dropdown menu. This is not my FIRST start, maybe the 5th or 6th. I will post my AS FOUND tune, as well as the UPDATED_INJECTOR DATA. read below

(https://forum.hptuners.com/showthrea...-in-ls1-format - used Eaglegoat's data)

As_found.hpt
Updated_injector_data.hpt
FIRST_RUN.hpl
SECOND_RUN.hpl

FIRST RUN was with AS FOUND tune - SECOND RUN was with UPDATED INJECTOR DATA tune

edit: FIRST RUN the breather line from the passenger side valve cover was vented to atmosphere, I fixed that and plumbed it into the intake air hose for SECOND RUN. Thought that might be important information to add from a data standpoint.


So what I am looking to get out of this post is for someone to look over the tune and let me know if there's anything way out of wack or something that is set wrong that could cause me to chase my tail or just have a negative impact. The ONLY thing I have done to the tune is the injector data and adjust the fan on/off temps. (I think the tahoe would've been fan clutch but I have twin e-fans and those temps were at 284 degrees)

The swap was purchased off CL as a complete STOCK engine/STOCK trans/pcm that someone had already turned VATS off and who knows what else, hence why I am seeking the advice and making sure some yahoo didn't go in a change a bunch of other stuff too that could be detrimental. ALL of the engine and transmission rebuild was performed by stepdad and I.

I have MPVi3 with the pro link, and an SM-AFR wideband but have not used it yet. ...

Thanks in advance for any help ya'll are willing to provide,
Doug-

[SiriusC1024]

STFT's are massively over-compensating. Assuming your injector data is correct you need to work on your VE table.

You're welcome to try mine or use it as a reference. It's dyno tuned. Kinda similar specs. You really should get a wideband before you open it up.

Howards 197245-12 - .525/.525 219/[email protected] 108CL 112LSA

[dtrev]

Oh geez yeah I forgot to put that I do have a PLX SM-AFR -_- I added that info to my original post.

Thank you for your response and the tune you provided, I will definitely use that as a reference!6

[blindsquirrel]

When I do the conversion manually from a stock Gen 4/L96 file for injector data I get substantially different numbers. Compare:

Updated_injector_data - blindsquirrel's 12613412 data.hpt

BUT - this is only correct IF you are using a 'returnless'/non-referenced fuel system and at 58psi - but you didn't mention even a single thing about the fuel system in your run-down up above. If you have a regulator with a vacuum line going to it (or it's using a base pressure other than 58), the injector tables have to be changed to account for that.

[Wolffots]

Just like the other guys said your injectors are going to be your biggest issue, I'm surprised it even started and idled given your modifications and a close to stock tune. You have essentially doubled the injector size from the stock 4.8 and have altered the cylinders, the ECU is going to struggle trying to figure out how to compensate. Hopefully the data that was provided from the other guys would help but if you are still struggling then it may be worth it to cut losses and get a set from a gen 3 vehicle that will be easier to find data for and start off with.

Definitely get the wideband working where you can log and see exactly how far off you are from commanded instead of relying of fuel trims and then set the car in either Speed density or MAF only and start carefully working on those tables to get them close to where they need to be.

Other minor things I would look at:
-disable cats, AIR, EGR IF they are not installed
-adjust PE to come on sooner
-set high octane spark table to match low octane until you can get fuel trims under control to help fight knock.

Good luck! We have a 4.8 swapped s10 and that thing is an absolute blast to drive

[blindsquirrel]

It's not difficult to convert Gen 4 injector data. There's a spreadsheet that works for early E38/E67s, and it can be done manually in about 20 minutes for later Gen 4s that don't have the right axis labels for the spreadsheet. https://forum.hptuners.com/showthrea...l=1#post700901

[Wolffots]

Oh cool! Thank you for sharing

...you enjoy that QR code don't you?

[dtrev]

Just like the other guys said your injectors are going to be your biggest issue, I'm surprised it even started and idled given your modifications and a close to stock tune. You have essentially doubled the injector size from the stock 4.8 and have altered the cylinders, the ECU is going to struggle trying to figure out how to compensate. Hopefully the data that was provided from the other guys would help but if you are still struggling then it may be worth it to cut losses and get a set from a gen 3 vehicle that will be easier to find data for and start off with.

Definitely get the wideband working where you can log and see exactly how far off you are from commanded instead of relying of fuel trims and then set the car in either Speed density or MAF only and start carefully working on those tables to get them close to where they need to be.

Other minor things I would look at:
-disable cats, AIR, EGR IF they are not installed
-adjust PE to come on sooner
-set high octane spark table to match low octane until you can get fuel trims under control to help fight knock.

Good luck! We have a 4.8 swapped s10 and that thing is an absolute blast to drive

Yeah I guess to give some back story the only reason I opted for those injectors is because the engine sat outside in the elements for several years before I got it, and the stock injectors were seized up from rust in the injector body. There was also standing water in the oil pan and rust on the main bearings and on the crank bearing surface itself. Which is what prompted the rebuild and blew my budget out of the water......lol

To be frank I was aware of them being gen 4 injectors but was not aware of a calculation difference, I will definitely look more into that and what others have said. I am aware of the significant injector size gain and have contemplated just biting the bullet for a stock gen 3 LR4/LM7 injectors. .

[dtrev]

When I do the conversion manually from a stock Gen 4/L96 file for injector data I get substantially different numbers. Compare:

Updated_injector_data - blindsquirrel's 12613412 data.hpt

BUT - this is only correct IF you are using a 'returnless'/non-referenced fuel system and at 58psi - but you didn't mention even a single thing about the fuel system in your run-down up above. If you have a regulator with a vacuum line going to it (or it's using a base pressure other than 58), the injector tables have to be changed to account for that.

Thank you for the info! I will examine your attachment and reply with any follow-up question after doing so separately.

2001+ 4cyl S10's were flex fuel and operated at 58psi (from what I found from several resources) so I have a new ACDelco stock fuel pump for the truck, and a corvette fuel filter. I verified I have 58psi at the rail with a mechanical gauge as well. How does not being 'returnless'/non-referenced change the situation?

[2xLS1]

It changes the way you set up the injector IFR table and Offset table.

[cobaltssoverbooster]

How does not being 'returnless'/non-referenced change the situation?

Its all about accounting for pressure differential changes. (rail pressure vs. manifold pressure)

The phenomenon: For this example assume the rail pressure is fixed at 58 psi. If your at idle with high vacuum, the maniofld vacuum is much lower that the rail pressure so naturally its easier to get fuel out of the injector (increased flow rate). When that vacuum drops, differential shifts making it harder to get fuel out the injector (reduced flow rate). Under boost, the manifold pressure pushes back on the injector making it even harder to get fuel out (major flow rate reduction).

To account for this with a non-referenced system, the computer injector section needs to include the repsective flow values for the varying manifold pressure conditions. Likewise, the offsets section having vacuum refrence axis also requires a lot of infromation to capture the dynamic flow variances of the injector in the same conditions.

When using a 1:1 referenced regulator, the mechanical function of the regulator will lower the rail pressure under idle and increase the pressure when the manifold vacuum drops off or goes into boost. It does this linearly, 1 psi of manifold rise equals 1 psi of rail pressure rise which is where it gets its name 1:1 regulator. Since all this flow dynamic is accounted for mechanically, the computer just needs to know the base flow rate and any offsets that occur based on voltage fluctuation. Basically the computer just needs to know that it doesn't need to account for flow rate changes. The regulator mechanically takes care of that.

Hope that helps.

[blindsquirrel]

screenshot.13-11-2022 19.49.13.png

[dtrev]

Ahhh ok I see, that makes sense. Blindsquirrel so being that I have the corvette filter/regulator that is not referenced but is a return style. That still puts me in the non-referenced style table (forgive my terminology) you posted, correct?

[blindsquirrel]

It's the presence or absence of the vacuum hose that makes the difference, not whether the excess fuel is vented through an external hose or is dumped direct from the pump module inside the tank.