1996 Chevy 7.4L - 0411 swap

[Mangonesailor]

Found ENG-1 fuse blown. another GMT400 thread said that could be an issue. starting up now on his 0411

[Mangonesailor]

THAT WAS IT! He's running now and we have feedback from MAF, going for a test drive now.

[Obsolete489]

Hell yeah!! Keep me posted!

[Oleblu]

So good ground, 12 volts to power the maf and the feedback wire has less than half an ohm resistance. Can you post the tune file. Did you guys poke the wire or pull the connector from the pcm and check the tip of the pin.

[Mangonesailor]

Hell yeah!! Keep me posted!

Ran great! It feels odd being on the passenger side and not feeling PE kick in at all like in my truck. I can also tell he has 3.73s. But other than that, ran great. I ended up taking his tune, putting in the VE table that Lextech gave me, made other things match up that you had set up, my cylinder displacement (very close to yours actually) and idle tables (speed/advance/offsets), and then your spark tables as a base line. I also enabled PE above 2700RPM and >50% throttle. I figured that'd give him something in case he's hauling and needs it. We ran a log and it does function, but I had to play with Torque management and allow it to build the max for it to function (what I had to do with my truck). He's aware he needs a wideband next to actually tune the truck.

I'll post the tune he had later and you can take a look at it. The spark table was VERY SURPRISING and I was not wanting to leave it in there like that.

So good ground, 12 volts to power the maf and the feedback wire has less than half an ohm resistance. Can you post the tune file. Did you guys poke the wire or pull the connector from the pcm and check the tip of the pin.

We didn't have 12v. We had 5v on the yellow wire (probably feedback from ECU), but nothing on pink. I thought pink at the time (brain fart, should've known it was 12v switched) was feedback to the PCM. So backprobing it I got no power or any sort of frequency off of it (read with fluke meter).

So I ended up googling "GMT400 0411 swap MAF no signal" and the top result was someone on GMT400 with the same issue and ENG-1 fuse was popped. We looked and sure-enough it was popped. Swapped fuses, re-taped some wires, and it ran like it should.

[BNielsen]

Mobbed the truck around a little more tonight, it's running great! I'm really kicking myself for not catching that fuse, I checked the fuse box 3 or 4 times while trying to trouble shoot everything.

Hopefully within the next couple of months I can cough for for a wideband, AFR gauge, and buy the HPTuners program so I can start playing around with everything. I've got some maintenance and a few interior things I've been putting off to take care of first.

Thanks again Mangone!

[Oleblu]

Lol I came in late on that one. glad it's running right again.

[Obsolete489]

Ran great! It feels odd being on the passenger side and not feeling PE kick in at all my my truck. I can also tell he has 3.73s. But other than that, ran great. I ended up taking his tune, putting in the VE table that Lextech gave me, made other things match up that you had set up, my cylinder displacement (very close to yours actually) and idle tables (speed/advance/offsets), and then your spark tables as a base line. I also enabled PE above 2700RPM and >50% throttle. I figured that'd give him something in case he's hauling and needs it. We ran a log and it does function, but I had to play with Torque management and allow it to build the max for it to function (what I had to do with my truck). He's aware he needs a wideband next to actually tune the truck.

I'll post the tune he had later and you can take a look at it. The spark table was VERY SURPRISING and I was not wanting to leave it in there like that.



.

Mangone your truck has 265s and 4.1s right? I'm guessing those 285s with 3.73s soak up a lot of torque.

What was going on with the spark map?

Really happy you guys figured it out.

[Mangonesailor]

4-13-19 brody 1 run with bastard tune.hpl
Bowtiebrody 1st hopped up tune with my stuff and obsolute timing.hpt
Bowtiebrody 2nd tune with IAT spark correction aggressive.hpt
Misfires and tuning.Channels.xml

For the sake of everyone checking this out, here's what he's running now, and an initial change I have ready for him to get that KR to calm down. Also the channel config is posted.

Hit 62% Inj duty cycle on stock injectors, HP tuners logged 375lbf at 2700rpm, but that's only 58% throttle, just to see if PE kicked in.


Below is what lextech gave him...
Bowtiebrody original from Lextech.hpt

Mangone your truck has 265s and 4.1s right? I'm guessing those 285s with 3.73s soak up a lot of torque.

What was going on with the spark map?

Really happy you guys figured it out.

My truck has 285/75R17's, with aluminum wheels. And yes, with 4.1s.

I'm happy too that it was simple and we got it taken care of.

[Obsolete489]

4-13-19 brody 1 run with bastard tune.hpl
Bowtiebrody 1st hopped up tune with my stuff and obsolute timing.hpt
Bowtiebrody 2nd tune with IAT spark correction aggressive.hpt
Misfires and tuning.Channels.xml

For the sake of everyone checking this out, here's what he's running now, and an initial change I have ready for him to get that KR to calm down. Also the channel config is posted.

Hit 62% Inj duty cycle on stock injectors, HP tuners logged 375lbf at 2700rpm, but that's only 58% throttle, just to see if PE kicked in.


Below is what lextech gave him...
Bowtiebrody original from Lextech.hpt




My truck has 285/75R17's, with aluminum wheels. And yes, with 4.1s.

I'm happy too that it was simple and we got it taken care of.

You guys really changed up that timing compared to the original.. I'm really surprised that what lextech ran it like that.. Also surprised by the PE settings. Were you seeing any kr with the original tune?

If you hit 62% dc down low in the rpms, I'd say its going to be getting up there at high rpm. I know the injectors are new replacements, but the one truck i tuned with stock injectors hit essentially 100% dc at high rpm.

[Mangonesailor]

Even a stock 8.1 tune doesn't run timing graphs like that. My original graph wasn't even like that either!

Original Biggin lextech 28lb tune.hpt

It didn't feel bad, but felt weak when accelerating honestly with the original tune he had. With the hodgepodge one it felt a little stronger, but not a whole lot of difference. I did not take a log set with his original tune. I should have, but we were mostly concerned about if it would run and stay running.

Maybe I'll throw that chart in my truck and see what happens. It's still very odd to me though.

What's surprising about the PE? as far as I could figure that's GM's settings for a 454, the 8.1's is very rich though in PE. O2s showed he was going rich and staying there. So I felt OK with leaving PE enable-able.

If I had a 1/4mi I could play with I'd make my own PE eq for myself. From other postings I've read from long ago HPtuner's HP and torque calc is fairly accurate as far as the trend it follows in regards to actual output (Note, to the wheels. Hptuners is already taking into account torque loss via the trans), but offset from the actual has to be figured out by putting it on a dyno and making that calculation.

Yeah, he will need injectors to make real power. I'm hitting somewhere around 70-ish with 28lbs, but my FPR is messed up and I'm only getting about 40-45psi. I'm not interested in replacing it again with another stock unit and will be installing an AEM unit in the future so I can have higher, and consistent, pressures. I can also adjust on the fly with it.

[Obsolete489]

Even a stock 8.1 tune doesn't run timing graphs like that. My original graph wasn't even like that either!

Original Biggin lextech 28lb tune.hpt

It didn't feel bad, but felt weak when accelerating honestly with the original tune he had. With the hodgepodge one it felt a little stronger, but not a whole lot of difference. I did not take a log set with his original tune. I should have, but we were mostly concerned about if it would run and stay running.

Maybe I'll throw that chart in my truck and see what happens. It's still very odd to me though.

What's surprising about the PE? as far as I could figure that's GM's settings for a 454, the 8.1's is very rich though in PE. O2s showed he was going rich and staying there. So I felt OK with leaving PE enable-able.

If I had a 1/4mi I could play with I'd make my own PE eq for myself. From other postings I've read from long ago HPtuner's HP and torque calc is fairly accurate as far as the trend it follows in regards to actual output (Note, to the wheels. Hptuners is already taking into account torque loss via the trans), but offset from the actual has to be figured out by putting it on a dyno and making that calculation.

I'm not sure how he ended up with it like that, very strange.

And I meant that lextech left the PE enable at 90%, and had the delay so high, just not how I'd set it. I'm sure it won't be a problem running it with PE enabled, might just leave a little power on the table not having the fueling exact. I don't think it'll hurt anything if it goes a touch lean, the factory tune ran it at WOT with a 14.7 afr for a minute lol

I really would like to spend a day playing on a dyno to find MBT and the best EQ for these engines, as well as see how the torque output lines up. I tried doing pulls using 12.2, 12.5, and 12.8 afr on my truck and it seemed like 12.5 yielded the most airflow so that's what I've stuck with, but that's far from scientific.

[Mangonesailor]

And I meant that lextech left the PE enable at 90%, and had the delay so high, just not how I'd set it. I'm sure it won't be a problem running it with PE enabled, might just leave a little power on the table not having the fueling exact. I don't think it'll hurt anything if it goes a touch lean, the factory tune ran it at WOT with a 14.7 afr for a minute lol

I really would like to spend a day playing on a dyno to find MBT and the best EQ for these engines, as well as see how the torque output lines up. I tried doing pulls using 12.2, 12.5, and 12.8 afr on my truck and it seemed like 12.5 yielded the most airflow so that's what I've stuck with, but that's far from scientific.

I requested from him when I got my initial tune that he turn down PE to "zero" but as-in allow it to come on. He basically said "You don't do that." It is rather dangerous if the VE and MAF are not remotely close to being the actual settings of the vehicle, and someone goes into the PE and runs crazy lean. Knowing that between your VE graph and mine and how his MAF looked i think his tune is a viable baseline. And true, I have done plenty of WOT runs in my truck before tuning. 14.7 at WOT doesn't kill it... but it's not really ideal... nor does it make power (makes noise, but doesn't move anything).

I think I'm still leaving a lot of power on the table with my own pickup. I probably should re-tune the VE table since I've messed with spark so much since, but I think it'd be more worth while dyno tuning for some better power and torque (Adjust timing via the fuel timing addition table) then let it be I suppose. Heck, my peak torque is showing that it's around 3500-3700rpm, but apparently that value is skewed because I don't mess with my MBT table at all (since I haven't dyno'd it I have no real reason to). Virtual dyno is also not installing correctly on my computer after their latest update... so I have no real way to check anything.

[Obsolete489]

Yeah I'm not saying its anywhere near ideal not knowing if the fueling is on point, nor would i be doing a bunch of WOT pulls, but it's probably fairly safe. If you do ever get yours on a dyno, I'd be really curious to see what it wants for MBT and if its an achievable value before running into KR.

[Mangonesailor]

Yeah I'm not saying its anywhere near ideal not knowing if the fueling is on point, nor would i be doing a bunch of WOT pulls, but it's probably fairly safe. If you do ever get yours on a dyno, I'd be really curious to see what it wants for MBT and if its an achievable value before running into KR.

Oh yes, I will post results once I get them. One of these days. Maybe sooner... it'll be my birthday soon. I need to do something for myself. There's a rentable dyno pretty close to me that I could get some numbers on I think.

[Obsolete489]

That would be an awesome birthday present lol I have one nearby that I keep telling myself I'm going to schedule some time on if/when i get my pickup to a point that I'm going to leave it alone for awhile.

[BNielsen]

Okay so it's been a couple weeks driving around with the 0411, and I've got to say, well worth all the trouble! There's still a couple quirks that are present such as sometimes it'll take a few resolutions to crank whereas other times it fires right off, and occasionally after it's been below 50 degrees it'll bog a little when I pull it in gear and give it a little throttle, but it smooths out almost immediately.
I assume both of these are just little things that need to be tweaked, I'll be getting an AFR gauge, wide-band, and hopefully MPVI2 in the next couple of weeks.

[Obsolete489]

I'm glad that it's going better now lol

[Mangonesailor]

Yeah, that bog is likely throttle cracker. I modified my table, but not yours. I thought it was brought on by my headers or ignition. Looks like I was wrong.

One thing I do think helps is running in open loop without STFTs when the engine is cold. You get to run a little richer (like you have a choke) and it works well, for me at least.

Not sure about the starting deal, but It could be cranking VE. I use a calculator I picked up off the forums to.make mine. I don't often have issues unless there's an actual problem (dizzy cap burnt up, bad injector). But I also have a gear reduction starter, so I spin over fast.

[Anthoney456]

Attachment 88715

Didn't get to it right away this morning, I helped remote tune this truck. 100% stock with an 0411, used a wideband to tune VE and MAF. Hope this is what you were looking for Mangone.

this was a 7.4 w 80e 411 swap all factory... what base tune did you use