Growing up doesn't have to suck

[iamdub]

ive always heard to do a write entire when you first unlock an ecm. there's thousands of tables beyond what hptuners can change. the idea is to write the entire ecm tune as its interpreted by hptuners. that way when you make changes in hptuners everything you "cannot see" plays nicely. ie if spark in xyz scenario effects table 23432423523.01, if hptuners interprets that table as 23432423523.1 it will cause problems

I did write entire the first couple of times I made changes, but then noticed I had the option to not write and figured there was no need to keep flashing something with no changes. Did I do this correctly or should I just write entire every time? FWIW, the only changes I made were the tire circumference and setting all EVAP errors to non-reporting.

 

[randeez]

Heeyago:

View attachment 271798


Is that abrupt jump in numbers at 1,600 RPM normal?

usually done if theres issues with it returning to idle, on coast down or something... cam related usually.
theres an entire table for idle spark and the transition between the tables sometimes causes problems. that 24 prob matches whats in the idle timing table

 

[randeez]

I did write entire the first couple of times I made changes, but then noticed I had the option to not write and figured there was no need to keep flashing something with no changes. Did I do this correctly or should I just write entire every time? FWIW, the only changes I made were the tire circumference and setting all EVAP errors to non-reporting.

nope youre good after the first time usually

or if a write cal fails in the middle of writing, go back and write entire

 

[iamdub]

lol, spark airmass is used because you can be doing 6000rpm in neutral with no load, or you can be doing 6000rpm in 4th going 150mph, the load is drastically different. its the value given for the time it takes for the fuel to ignite or someshit. just log it and use it for reference when your making changes

Roger that.

 

[iamdub]

What's your cr? I know you went for max quench to avoid kr. might be able to squeeze some more timing out of it.


the 24* around idle is supposed to help with stalling, idk anything about converters but maybe yours flashes right there and can take more timing or something. That low airmass high timing is kinda odd-looking to me but idk anything about gen 4 or autos lol.

I'd like to know what I'm looking at to know just how conservative it is. I told the tuner he didn't have to be shy with the timing since I only run good gas and upped the quench for this purpose. After a couple of hits with him slowly adding timing, among other adjustments, he seemed slightly surprised when he felt that he could add even more. Maybe I had better quality gas than what he was expecting or maybe upping the quench made that much a difference or both.

As for timing at idle in P or N, he set it to lope as much as feasible, per my request. Does that explain anything? My converter is a 2,600-2,800 but he said it seemed to be flashing to 3,000.

 

[iamdub]

nope youre good after the first time usually

or if a write cal fails in the middle of writing, go back and write entire

Tracking.
That's why I have a baseline saved in multiple media forms in multiple places and why I'm keeping a journal. I know there's places to leave notes on the files themselves, etc., but I'm a pen-and-paper guy. I like being able to write as much as I want up, down and sideways; draw arrows, underlines, hearts and stars and other doodles, etc.

 

[randeez]

As for timing at idle in P or N, he set it to lope as much as feasible, per my request. Does that explain anything? My converter is a 2,600-2,800 but he said it seemed to be flashing to 3,000.

probably, the loop is caused by making too much torque at idle (by adding timing) to the point where theres not enough air to continue to let the rpm rise, chokes, idle rpm falls back down. however what happens is, one the parameters to kick it off of the idle timing map to the high octane timing map is when it sees x-change in vacuum so much over y-amount of time. you set a target rpm error that the ecm will try and maintain.
the issues - if you have too much idle timing you dont get a "rpm bump", youll see people call it reserve timing sometimes, this is noticeable if you get bogging while putting it in gear, ac compressor engaging, turning full lock power steering strain, coming off idle. scenarios where you're idling but the engine needs a little more power.
theres plenty of paths to get to the end result. looking at just the main spark table doesnt tell the whole story

 

[iamdub]

probably, the loop is caused by making too much torque at idle (by adding timing) to the point where theres not enough air to continue to let the rpm rise, chokes, idle rpm falls back down. however what happens is, one the parameters to kick it off of the idle timing map to the high octane timing map is when it sees x-change in vacuum so much over y-amount of time. you set a target rpm error that the ecm will try and maintain.

I'm gonna have to read over this a few more times and imagine the dynamics in my mind. But, from what I'm understanding about the "not enough air" part, would mean a rich idle, yeah? Cuz mine be smelly! No cats makes it worse. So, if I had it tuned to be as smooth as possible, like stock at idle, then the raw fuel smell would be much less?

the issues - if you have too much idle timing you dont get a "rpm bump", youll see people call it reserve timing sometimes, this is noticeable if you get bogging while putting it in gear, ac compressor engaging, turning full lock power steering strain, coming off idle. scenarios where you're idling but the engine needs a little more power.
theres plenty of paths to get to the end result.

As far as issues from a sudden load at idle, I have none. The idle rises slightly and smooths out immediately when put in gear, when the A/C engages, etc. When idling with the A/C on, it smoothly transitions from loping to steady as the compressor cycles. So, I guess he has me set pretty good there.

looking at just the main spark table doesnt tell the whole story

I'm sure of this, I just didn't know which screenshots were pertinent to post up. Or, do you care to look at my tune?

I'm starting to feel like I'm at a dick doc's office, walking around with my pants down and asking all the docs and nurses if they wanna check out my ****** to tell me if they think it looks infected.

 

[randeez]

not necessarily.... the fueling will be controlled by the maf, whatever value it reads it fuels for. with the TPS is constant, if you advance or retard timing rpm will rise or fall. so you have an rpm window that the engine will run in for a given tps position.

basically if i have the tps open enough to supply 20lbs of air to the engine:
at 500rpm the engine gets plenty of air but has 2psi of vacuum and idles horrible.
at 1000rpm has great idle and 20psi of vacuum,
at 1500 rpm not enough air and chokes

problem being is gen4 ecm will try and target idle rpm by moving the throttle and spark at all together at once

the maf makes idle tuning 100x easier because youre not ALSO trying to fuel based on manifold pressure and rpm. with a cam you get reversion back into the cyclinders and the vacuum reading doesnt correlate to the correct fueling needed

 

[Dantheman1540]

I'm gonna have to read over this a few more times and imagine the dynamics in my mind. But, from what I'm understanding about the "not enough air" part, would mean a rich idle, yeah? Cuz mine be smelly! No cats makes it worse. So, if I had it tuned to be as smooth as possible, like stock at idle, then the raw fuel smell would be much less?




As far as issues from a sudden load at idle, I have none. The idle rises slightly and smooths out immediately when put in gear, when the A/C engages, etc. When idling with the A/C on, it smoothly transitions from loping to steady as the compressor cycles. So, I guess he has me set pretty good there.




I'm sure of this, I just didn't know which screenshots were pertinent to post up. Or, do you care to look at my tune?

I'm starting to feel like I'm at a dick doc's office, walking around with my pants down and asking all the docs and nurses if they wanna check out my ****** to tell me if they think it looks infected.

I wouldn't mind looking at the tune although I doubt I will be helpful I like building my personal tune repository to reference later on.

As for max spark being around 25* since we don't have a data log showing KR and showing actual spark* to review alongside with the targeted table its impossible to know if it could take more or less. On top of that, the only true way to tune spark is on a dyno and watch the torque curve.

But If it's showing 3*kr at 5800rpm it's safe to assume 25* is too much and you need to back it down 3* or more. Not saying you have any KR we just don't know given the current data. Also if you are showing not KR whatsoever across the board you could sprinkle a * or ** across the board and see what that does.

 

[iamdub]

not necessarily.... the fueling will be controlled by the maf, whatever value it reads it fuels for. with the TPS is constant, if you advance or retard timing rpm will rise or fall. so you have an rpm window that the engine will run in for a given tps position.

basically if i have the tps open enough to supply 20lbs of air to the engine:
at 500rpm the engine gets plenty of air but has 2psi of vacuum and idles horrible.
at 1000rpm has great idle and 20psi of vacuum,
at 1500 rpm not enough air and chokes

problem being is gen4 ecm will try and target idle rpm by moving the throttle and spark at all together at once

the maf makes idle tuning 100x easier because youre not ALSO trying to fuel based on manifold pressure and rpm. with a cam you get reversion back into the cyclinders and the vacuum reading doesnt correlate to the correct fueling needed

I wouldn't mind looking at the tune although I doubt I will be helpful I like building my personal tune repository to reference later on.

As for max spark being around 25* since we don't have a data log showing KR and showing actual spark* to review alongside with the targeted table its impossible to know if it could take more or less. On top of that, the only true way to tune spark is on a dyno and watch the torque curve.

But If it's showing 3*kr at 5800rpm it's safe to assume 25* is too much and you need to back it down 3* or more. Not saying you have any KR we just don't know given the current data. Also if you are showing not KR whatsoever across the board you could sprinkle a * or ** across the board and see what that does.

Yeeeeah. I'm just gonna stick to oil changes and tire rotations.

 

[Dantheman1540]

Yeeeeah. I'm just gonna stick to oil changes and tire rotations.

No it's to late your already infected! Keep learning and asking questions!


It helps me learn!

 

[iamdub]

Since a few terrible influencers including @pwtr02ss talked me into building my own trans, I've been on the lookout for a good core. An ad for an '08 Tahoe being parted popped up a week or so ago. A guy bought it from an insurance auction for rear body parts, got what he needed and was parting out the rest before scrapping. He said he has to assume the trans was junk and would take $100 for it. What are the chances of me finding a rebuildable Gen4 4L60E in my little town for $100?! I messaged him with the commitment to buy. He had a buyer for the engine and trans as a combo ahead of me but would call me first if it fell through. Well, that guy was a no-show and someone else claimed the engine, so the trans was available and already pulled since they pulled them together. I went that next afternoon to claim my prize.

When I got there, I saw that the trans looked like shit. Not that I cared since I'd be cleaning and painting the case, but it had a light green moss haze on the top, indicating it had sat out in the weather, uncovered for some time. He told me that when they pulled everything, the trans was bolted to the engine by just the bottom four bolts and the torque converter wasn't bolted to the flywheel. Obviously, this trans was not original to the Tahoe nor was the Tahoe ever driven with it.

At the time, I didn't know about deciphering the tag on the case nor anything else to verify it was a Gen4. But, it looked like one and I had already told him to consider it sold. I wasn't gonna back down from my word so I took it home.

I ran numbers and spent a couple hours researching and started to suspect it was actually a Gen3. The next morning (yesterday), I popped off the pan (half the bolts were missing and the existing ones were hand-tight) to look for the Input Speed Sensor (ISS).

Pics from yesterday morning-

This is right after I removed the pan. No filter to be found it had water in the pan, among other contaminants:

...Contaminants such as leaves, pine needles and dirt:

Watery oil (or oily water?) and what appears to be an expected amount of metal on the magnet:

As expected, the ISS was not there, confirming that this WAS a Gen3 trans. BUT, the hole where the ISS goes was there and had a factory cap secured by a snap ring, so it's not like I'll have to drill out a cast-in blank or machine a hole, etc. to add the ISS:

I really don't care about the filth since all I need is an undamaged case with good internal hard parts, and, so far, I still believe I have that. I'll be replacing the major parts with upgraded ones and the rest will be new upgraded normal wear items (clutches, steels, etc.). What I'm trying to do at this point is verify that the only difference between this Gen3 and a Gen4 is the addition of the ISS. This one is an '07, but from the "Classic" body style. As far as I know, I'll need the ISS, the internal harness (was getting a new one, anyway) and the correct pump (this part stings a little, but whatever). I MIGHT need the later input shaft if this one doesn't have the reluctor on it. In the meantime, I'm still keeping a look out for a cheap and rebuildable true Gen4 4L60E.

 

[Tonyrodz]

Since a few terrible influencers including @pwtr02ss talked me into building my own trans, I've been on the lookout for a good core. An ad for an '08 Tahoe being parted popped up a week or so ago. A guy bought it from an insurance auction for rear body parts, got what he needed and was parting out the rest before scrapping. He said he has to assume the trans was junk and would take $100 for it. What are the chances of me finding a rebuildable Gen4 4L60E in my little town for $100?! I messaged him with the commitment to buy. He had a buyer for the engine and trans as a combo ahead of me but would call me first if it fell through. Well, that guy was a no-show and someone else claimed the engine, so the trans was available and already pulled since they pulled them together. I went that next afternoon to claim my prize.

When I got there, I saw that the trans looked like shit. Not that I cared since I'd be cleaning and painting the case, but it had a light green moss haze on the top, indicating it had sat out in the weather, uncovered for some time. He told me that when they pulled everything, the trans was bolted to the engine by just the bottom four bolts and the torque converter wasn't bolted to the flywheel. Obviously, this trans was not original to the Tahoe nor was the Tahoe ever driven with it.

At the time, I didn't know about deciphering the tag on the case nor anything else to verify it was a Gen4. But, it looked like one and I had already told him to consider it sold. I wasn't gonna back down from my word so I took it home.

I ran numbers and spent a couple hours researching and started to suspect it was actually a Gen3. The next morning (yesterday), I popped off the pan (half the bolts were missing and the existing ones were hand-tight) to look for the Input Speed Sensor (ISS).

Pics from yesterday morning-

This is right after I removed the pan. No filter to be found it had water in the pan, among other contaminants:

View attachment 271836


...Contaminants such as leaves, pine needles and dirt:

View attachment 271837


View attachment 271838


Watery oil (or oily water?) and what appears to be an expected amount of metal on the magnet:

View attachment 271839


As expected, the ISS was not there, confirming that this WAS a Gen3 trans. BUT, the hole where the ISS goes was there and had a factory cap secured by a snap ring, so it's not like I'll have to drill out a cast-in blank or machine a hole, etc. to add the ISS:

View attachment 271835



I really don't care about the filth since all I need is an undamaged case with good internal hard parts, and, so far, I still believe I have that. I'll be replacing the major parts with upgraded ones and the rest will be new upgraded normal wear items (clutches, steels, etc.). What I'm trying to do at this point is verify that the only difference between this Gen3 and a Gen4 is the addition of the ISS. This one is an '07, but from the "Classic" body style. As far as I know, I'll need the ISS, the internal harness (was getting a new one, anyway) and the correct pump (this part stings a little, but whatever). I MIGHT need the later input shaft if this one doesn't have the reluctor on it. In the meantime, I'm still keeping a look out for a cheap and rebuildable true Gen4 4L60E.

At least you're a man of your word. That's rare today.

 

[Sam Harris]

Since a few terrible influencers including @pwtr02ss talked me into building my own trans, I've been on the lookout for a good core. An ad for an '08 Tahoe being parted popped up a week or so ago. A guy bought it from an insurance auction for rear body parts, got what he needed and was parting out the rest before scrapping. He said he has to assume the trans was junk and would take $100 for it. What are the chances of me finding a rebuildable Gen4 4L60E in my little town for $100?! I messaged him with the commitment to buy. He had a buyer for the engine and trans as a combo ahead of me but would call me first if it fell through. Well, that guy was a no-show and someone else claimed the engine, so the trans was available and already pulled since they pulled them together. I went that next afternoon to claim my prize.

When I got there, I saw that the trans looked like shit. Not that I cared since I'd be cleaning and painting the case, but it had a light green moss haze on the top, indicating it had sat out in the weather, uncovered for some time. He told me that when they pulled everything, the trans was bolted to the engine by just the bottom four bolts and the torque converter wasn't bolted to the flywheel. Obviously, this trans was not original to the Tahoe nor was the Tahoe ever driven with it.

At the time, I didn't know about deciphering the tag on the case nor anything else to verify it was a Gen4. But, it looked like one and I had already told him to consider it sold. I wasn't gonna back down from my word so I took it home.

I ran numbers and spent a couple hours researching and started to suspect it was actually a Gen3. The next morning (yesterday), I popped off the pan (half the bolts were missing and the existing ones were hand-tight) to look for the Input Speed Sensor (ISS).

Pics from yesterday morning-

This is right after I removed the pan. No filter to be found it had water in the pan, among other contaminants:

View attachment 271836


...Contaminants such as leaves, pine needles and dirt:

View attachment 271837


View attachment 271838


Watery oil (or oily water?) and what appears to be an expected amount of metal on the magnet:

View attachment 271839


As expected, the ISS was not there, confirming that this WAS a Gen3 trans. BUT, the hole where the ISS goes was there and had a factory cap secured by a snap ring, so it's not like I'll have to drill out a cast-in blank or machine a hole, etc. to add the ISS:

View attachment 271835



I really don't care about the filth since all I need is an undamaged case with good internal hard parts, and, so far, I still believe I have that. I'll be replacing the major parts with upgraded ones and the rest will be new upgraded normal wear items (clutches, steels, etc.). What I'm trying to do at this point is verify that the only difference between this Gen3 and a Gen4 is the addition of the ISS. This one is an '07, but from the "Classic" body style. As far as I know, I'll need the ISS, the internal harness (was getting a new one, anyway) and the correct pump (this part stings a little, but whatever). I MIGHT need the later input shaft if this one doesn't have the reluctor on it. In the meantime, I'm still keeping a look out for a cheap and rebuildable true Gen4 4L60E.

Holy shit! That thing went through the wringer! But I still say that’s a hellova bargain! I know you’re replacing a lot of it, but you were planning to anyway. Too bad about the ISS, but I think it will still be a great deal overall. And I can’t wait to see this done!! Wish I had the guts, time, skills, and tools to do this myself.

 

[Dantheman1540]

Thos is awesome! You are allowed a break from tuning to build the trans lol.

 

[iamdub]

At least you're a man of your word. That's rare today.

I'm a strong believer in karma. He didn't know anything about the trans until it was pulled with the engine and I (as well as he) assumed up until that point that it was original to the Tahoe. I kinda jumped the gun in my excitement for thinking I found such a deal on a Gen4, so that's on me. At $100, I kinda wasn't overly concerned since cores are usually $200-$300. I could probably sell it to a rebuilder for $100 if I really just wanted to offload it and start over. It's not the deal I thought I was getting, but it's not a loss, so I'm content with that.

From everything I've seen, it looks like the PO of the Tahoe took their trans out and put this one in its place so insurance wouldn't deduct it from their settlement. The one they kept may have been replaced or rebuilt not long before the Tahoe was wrecked so they didn't wanna let it go with the Tahoe. It happens all the time, just usually with wheels, radios, etc. That's why you find stock radios in the dashes at the salvage yards that aren't even hooked up, they're just there for looks and sometimes aren't even from that brand of vehicle. Someone just threw "a" transmission in there so it'd be "complete".

I thought of something earlier: That guy said he also had an '07 GMT900 Avalanche, but it was 4WD. I'm gonna check with him on the trans from that one and maybe work up a deal. You can convert a 4WD to 2WD and vice versa by swapping the output shaft and tailhousing. Swapping the shaft requires a complete disassembly, which it's getting anyway. So, my Gen3 trans could end up being a $100 conversion kit (cheap) as well as a guinea pig for practicing and/or spare parts supply.


I'm reminded of this quote:

 

[iamdub]

Holy shit! That thing went through the wringer! But I still say that’s a hellova bargain! I know you’re replacing a lot of it, but you were planning to anyway. Too bad about the ISS, but I think it will still be a great deal overall. And I can’t wait to see this done!! Wish I had the guts, time, skills, and tools to do this myself.

I've always shied away from transmissions. Diving into one has never interested me at all because there is so much to learn and so much that could go wrong and thousands of dollars and hours of work can be wasted over a 25¢ part not meeting a .001" tolerance...





















... But if a knuckle-draggin mouth-breather such as @pwtr02ss can build one, then so can I.

 

[iamdub]

Thos is awesome! You are allowed a break from tuning to build the trans lol.

Lol

Well, one thing I wanna tune is to reduce or remove Torque Management. I can't do that on a (supposedly) 200K-mile stock trans and expect to drive home. So, this needs to happen.

 

[Tonyrodz]

I've always shied away from transmissions. Diving into one has never interested me at all because there is so much to learn and so much that could go wrong and thousands of dollars and hours of work can be wasted over a 25¢ part not meeting a .001" tolerance...





















... But if a knuckle-draggin mouth-breather such as @pwtr02ss can build one, then so can I.