HT383e/0411 dyno tuned IFR @ 19 instead of 23.1lb/hr

Good day guys,

I had my truck (details below) dyno tuned a few weeks back and my local tuner changed my IFR from 23.1 to 19.1 on the Engine> Fuel> Injector Flow Rate versus KPA table,... then proceeded to go through a lengthy dyno/street tuning process.

I now know, the IFR was supposed to be 23.1 (instead of 19.1),... my question is; how is this affecting my engine/tune? Am I getting max power with a lower IFR? Will this lower IFR setting damage my engine? Apologies guys, I'm new,... but learning quickly.

Truck details;
1996 GMC K1500 4x4 ext cab
5.7L Vortec swapped to an HT383e/MPFI spider upgrade
Hedman Hustler long tube race headers with dual 2-1/2" ss exhaust
0411 PCM swap from Lextech (with his base tune)
Level 5 4L60e from FLT with Sonnax 3-4 drum upgrade (installing next week)
Rebuilt 3.73 rear axle with Detroit helical locker/Yukon axles and gear
The list goes on,...

Thanks Guys, I appreciate your advice.

whats the fuel pressure at?

Thanks for responding so quickly Area47.

It's 55-60psi,...key on/engine off is 60psi,...engine running it's 55-58psi depending on throttle movement/rpm.

I changed the fuel pump a couple months back (still had good pressure but, was starting to make noise, thus knew it was bout time). I did the leak down test (pressure test/regulator check) and observed psi while running.

Thanks for responding so quickly bud,...I truly appreciate it.

was the injectors in the tune rated at 42, or 58?

Thanks again Area47,... man your responses are fast.

I'm quickly learning but, still new to HPTuners/tuning bud,...the injectors are stock size,....I simply replaced the old CSFI poppet style injector spider with the new Delphi MPFI spider injector upgrade (popular for 96-99 Vortec trucks),...but they're still "as stock" flow rates.

From what I understand,... stock- they are 19lb/hr injectors, but flow 23.1lb/hr at 55psi. I've done the "compare tunes" feature within HPTuners, between my tune and several others in the HPTuners repository (for my years/compatible 5.7L trucks and vans),....... and they all have 23.1 in the "Injector Flow Rate vs KPA" table. I also contacted LexTech (pioneered the 0411 swap) and he said, "stock, the table should list 23.1 across the board."

Again, please excuse my dumbness bud,.... sometimes I feel/look like ol' Joe Dirt at the oil rig (spittin oil in my face) hollarin' "I'm new, I'm new",... ;)

But, learning very quickly,...I hope anyway,....

Thanks again for helping me Area47

you're doin just fine man. What i posted in the other thread is something that needs to be heeded. "it's time to find someone else" I would post the tune itself. i have a feeling there is more wrong than just the two things posted about so far.

Thanks Area47,...man your simply too quick. I wouldn't want to race you.

My tune will be attached in the next message (gotta figure out how to do it,...I'm Ol' Joe Dirt'in it again). Yes Sir, I agree more than words can say right now,...$500 for half-ass work,....hell, me being bent over don't even hurt anymore :secret:

Thanks for the help Area47,...I truly appreciate it man.

Attachment 68373

Here it is, I think anyway,..., yeah that's my tune file,...don't know how I just did that.

Here's my tune Ari666, Obsolete489 and DiceDaLova as previously requested on other posts,... thanks guys.

i'll take a look when i get a second. :)

Thanks Area47,...I truly appreciate you helping me man,...truly. I'm trying to learn as much/as quickly as I can. The curve is steep but, I'm running it hard. :cool:

Well, it doesn't look like he messed with other fueling parameters. It looks you'd just need to change the flow rate back to 23.1 then retune the VE and MAF. Do you run E10 or some blend? Just curious as to why he's commanding 14.5 AFR.

I can't say the VE and spark tables look bad, but I'm far from an expert. They appear stock with how smooth they are but when compared to the stock tables from an express van tune, they are indeed different. I know my VE table is not near that "nice" looking.

He did also disable a bunch of DTCs.

Attachment 68408Attachment 68409Attachment 68410Attachment 68411

Thanks 489, (that's got to be one impressive engine by the way)

Yes Sir, he spent a lot of time tuning VE/MAF on the dyno,... they do "look" very smooth don't they? But, admittedly,...I wouldn't know shit from shinola,... right now,..(but I'm learning). And I believe he set the AFR to 14.5 because we have an ethanol mix in our fuel around here in Central Florida (but, again, not 100% sure that's why).

LexTech just sent me two PCM's with both the - 100% stock 2002 Express van tune (5.7L/4L60e/4x4/3.73) - and the tune he modified for my HT383e/truck,...if you need them, PM me. I plan to put both of these on the HPTuners repository (once I learn how) so I can maybe provide a "little" help to the next new/experienced guy.
Lextech knew I couldn't find the base tune, and that my local tuner hadn't saved my base tune for me,...so, he sent me the two PCM's so I could download both into HPTuners format. Man, he hooked me up,...that's a good dude right there.

I can't wait to be "one of those guys" that can help new people on this forum,...Lord knows y'all have helped me a lot. I'm learning quickly/won't be long, thanks to y'all.

Thanks again 489.

It does alright, its really good at burnouts and consuming lots of fuel haha. I'm still trying to figure out exactly what it likes for timing and AFR at WOT, but it seems to pull fairly hard. I should dyno it sometime just to see where its at. I'm running stock heads and intake, so its not anything crazy. I'd love to swap on some aftermarket heads someday and do something different for the intake manifold, but man big block stuff is expensive.

So you now have 3 0411s? Licensing all 3? Thats a lot of credits to burn, but hopefully it'll work out for you.

I wonder if it'd work to scale the MAF and VE table by 17.7% to account for the injector differences? It'd probably get it close anyway.

Do I have to license them before I can upload them to the repository?

When I received the box (with two PCM's in it from LexTech), I installed each PCM in my truck (then reconnected battery ground), and downloaded the tune into HPTuners/saved each of them - one as "100% stock base tune" and the other as, "LexTech modified HT383e base tune".

They are now saved on my laptop under a VCM Editor folder,.... I used them to differentiate what was different between the 2 tunes LexTech sent me, and my existing tune using the "compare" feature (my local dyno tuner didn't save my original base tune before he started changing things - thus I didn't have a base to work from).

Hopefully, I wouldn't have to license them before I upload them to the repository (to help other people)? I've seen several people on here swapping to 0411 needing/requesting these exact tunes,...repository has these tunes for a 4L80e, but not for the 4L60e (which is what I have).

No, you shouldn't have to license them to upload them to the repository. And I understand what you meant now, I'm sure that'll make some people happy.

Looks like you just go to the customer page to upload.
Attachment 68431

Thanks 489,...cool,...I'll try it, should be easy to upload both tunes for fellow 0411 truck guys.

I wonder if scaling both VE and MAF by 17.7% would work?? Has anyone tried this,...or knows not to do it?

The old adage "you get what you pay for" doesn't apply here,....I paid top dollar for my dyno. I could see if I paid $200, that I may have an issue,....but, I paid $580, thus think he should make this right,...especially considering the wrong IFR was used AND my TCC table is way off.

My problem is, I don't know enough about "why" he should retune due to wrong IFR and TCC. If ya'll could give me some pointers as to "why", that would help. My local tuner is supposed to be back from vacation in a few days, I didn't want to bother him/his family,...so, just need the technical lingo behind the "why" before I make that call.

Man,....I dread making a phone call to him bout this,....but, I need to be ready just in case the smell of BS starts to permeate our immediate surroundings.

I mainly bought HPTuners for the scanner portion, in case something starts going wrong in the future, I could diagnose,...and maybe adjust my transmission shift points to my liking in the future,....but, glad I'm now learning the rest of this.

Thanks guys.

I would definitely call and see what he can do to make this right. And it'll be worth your time to learn the software and what goes in to tuning, otherwise you're sorta wasting it. Although if you don't change much else on the truck after it is retuned, you should be able to leave it alone aside from maybe messing around with the transmission.

Thanks 489,..yes sir, I fully intend on learning it now,...given my current local tuner issues. Lots to soak in,...I was up til 2:30am this morning researching/learning. I'll let y'all know what my local tuner says when I make the call,....wish I had the "it needs to be changed due to this reason" knowledge.

It could be as simple as scaling the VE and MAF, but it also might not be. Bottom line is, he needs to make the changes and at least check how the VE and MAF match up to actual airflow after the IFR is changed.

Hopefully he is reasonable and works with you. Good luck man.