5.3 Gt45 newb

[Jabootydawiz]

hey all, just wanted a few pointers and tweaks. Can barley turn a wrench so tuning my first build has been a learning experience.
here is the hardware : SBE 5.3 Lm7. 6.0 "317" heads. ebay ss2 cam, truck intake. ebay 80lbs inj (have data), gt45 turbo on like 5-8 lbs wastegate spring. Sno Meth inj triggered @ about 5 lbs. 2 walbro pumps(one is boost/meth triggered @ 5lbs) "y" to -6 then split to each rail, Boost ref reg to -8 return, stock L60. stock converter, stock gm 7.5 diff (g body)


Goal:just a fun lil sleeper. burnouts/brake stands, and small pulls. not trying to break records or any more parts than necessary although inevitable

Concerns: as it sits now, the idle in the tune is was way too rich. barley can stay idling wih afrs around 12.
at times, tip in acceleration will trend lean and even produce a "pop"
i think getting into boost afrs are rich but when im driving it it seems to be pulling decent. idk could be ive never felt "real" power. But were getting there!

here is the current "tune" plus a log i made this morning. had to cut it short due to a fuel leak.
Thanks for any advise toward my goal are appreciated
NUstkblnd2.hptoringoshit.hpl

[SiriusC1024]

First thing is to setup the fuel injector data for the boost-referenced regulator. That means 0kPa column values applied to the rest for Flow Rate and Offset.

[Jabootydawiz]

like this?

NUstkblnd 3.hpt

[SiriusC1024]

No. Like this.

Run a log with those settings applied.

[sanfriz]

I think it's the injectors. I have been chasing my tail with 80lb eBay injectors. My data matches yours. I had someone on here give me another data match and same results. I just ordered 95lb DEATSCHWERKS tonight to see if that fixes the problem. Hurt on a low budget build but on their website, I got 10% off so paid $650 for a set of 8 flow matched with GM data. I tried everything over the last few months, including another set of "authentic" deka 80 injectors to get my truck running right. I have the same cam but only 1 fuel pump. I know I'm not running out of fuel though. I did a compression test, leak down test, combustion test and those were all within spec. It hurts to put $650 injectors in a $300 engine but if it makes it run right it will be worth it. If not it's a gas can and matches

I followed all of the step-by-step instructions on YouTube, even subscribed to Evans Performance Academy to set it up right. I'm convinced my tune is good enough where it should be running better but it's not.

[RDF1]

Injectors are the most important part of the whole build. Everybody i see that skimps on injectors and get ebay specials either have idle issues or burnt up pistons.

[Jabootydawiz]

I Hear ya guys loud n clear. Ill buy myself some good injectors next! here is a log from the drive into work. using this tune
2WRKNOV9.hplvacuumreg#1.hpt

[Jabootydawiz]

vacuumreg#2.hpt2home.hpl


made new tune by taking afr err from 1st log and applied to ve. smoothed a few times n drove er home.

[SiriusC1024]

Well, see what happens.

[Jabootydawiz]

just a lil lean when throttle is cracked n way too rich going into boost.

2 airport.hpl

[SiriusC1024]

This can't be tuned. There are massive differences between cause and effect.

I compared a stock 2003 5.3 Tahoe file. Fuel>Transient>Fuel Boiling Time was different. I restored it, and that's the only change made here. It's only one table, but it should make a big difference. In the log I'm seeing that there's delay in requested fuel as well as magnitude of AFR error vs MAP.

Still, if it's not that then it's the injectors/data. From the wideband behavior I suspect the accuracy of the offset and short pulse. Please give me the number off the side of those injectors and the supplied datasheet.

...and a log

[gtstorey]

It was just a matter of time that Amazon and EBay counterfeit injectors would start coming with counterfeit data. And even if the data isn’t counterfeit, the injectors quality control means the data may not work anyway.

[edcmat-l1]

ebay 80lbs inj (have data)

As a business I decline to tune stuff like this. I do lose a certain amount of work by refusing to tune certain parts, but I also limit my headaches and liability. No sense trying to chase mystery injectors.

[Jabootydawiz]

Ok so injectors/data is the only problem is what you guys are saying...I?ll be back then In a few weeks with 600$ injectors in this 200$ engine 🥲 hopefully some progress will be made then.

[Jabootydawiz]

Are there any OeM options I could use? Some injectors I could possibly go snag from my local wrecking yard perhaps?

[gtstorey]

Maybe L94 injectors?

[SiriusC1024]

Hold on. Try the tune first. See what happens.

But yes I mentioned previously (in another post of yours) that the data they gave you is probably bs, and that they supplied it just to make the product look legit.

And if you need help spec'ing injectors I'd like to do that, too. Maybe there's a cheaper option out there than $600. Also, what boost target? L94 is a reasonable suggestion for low boost.

[Jabootydawiz]

sorry 4 delay

wrk1122.hpl

[SiriusC1024]

Hey that's looking much better. That transient table adjustment improved things greatly. There are still a few anomalies in the VE table, but if it's consistent then it's ok. Log some more.

[Jabootydawiz]

drive homewrkhme1122.hpl