Results 1 to 14 of 14

Thread: LS Jeep SD tuning help... please

  1. #1
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42

    LS Jeep SD tuning help... please

    I have a fresh build lm7 based engine. I have changed usual parameters for a cam swap but am having issues with starts still and want to know if I am on the right track/ what my next steps are. I have went into 1 bar SD OS and believe I have that all set up correctly. I have also set up an AFR error table and have been adjusting accordingly. The log I am attaching is my first drive in the jeep with a couple of pulls in 4 low since that is where this thing spends its time. The numbers are slightly off from where I thought I was perfect with my discovery of a vacuum leak (now fixed) I also played with my fueling adjustments and have 59 psi across the board. Jeep finally let me rev over 1200 rpms when in drive.

    My problems now are that I still have to rest my foot on the gas pedal to get it started for about 5 seconds. If i don't do this, it runs for about 3-5 seconds and shuts down. It does not act like it is going to die when I rev up in neutral and let the rpms drop, but does seem to occasionally want to shut off/lope when in gear.

    With my AFR error I took this data and paste special-mult by 50% into my VE table. Do I just keep driving and playing while logging and continuously do this until I get closer? Any help is appreciated and I am happy to atleast gotten to drive the thing and feel some good power.

    Engine is stock LM7 with exceptions of Summit 8706 stage 2 turbo cam, flat top pistons, and dual valve springs.
    Cam Specs:
    Summit Racing SUM-8706: Stage 2 Pro LS Turbo Cam. 226/230 Dur., 113+4, .600/.575 Lift, 3-bolt, 5.3, 5.7, 6.0, 6.2, 7.0, Vortec Truck, LS1 LS2 LS6 LS3 LS7 LQ4 LQ9 LS9, Each

    This motor is in my crawler with a th400 and np205 behind it with 4.56 gearing.

    Jeep field driving.hplJeep file idle updated (Speed Density).hpt

  2. #2
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42
    Quote Originally Posted by Daniel196 View Post
    I have a fresh build lm7 based engine. I have changed usual parameters for a cam swap but am having issues with starts still and want to know if I am on the right track/ what my next steps are. I have went into 1 bar SD OS and believe I have that all set up correctly. I have also set up an AFR error table and have been adjusting accordingly. The log I am attaching is my first drive in the jeep with a couple of pulls in 4 low since that is where this thing spends its time. The numbers are slightly off from where I thought I was perfect with my discovery of a vacuum leak (now fixed) I also played with my fueling adjustments and have 59 psi across the board. Jeep finally let me rev over 1200 rpms when in drive.

    My problems now are that I still have to rest my foot on the gas pedal to get it started for about 5 seconds. If i don't do this, it runs for about 3-5 seconds and shuts down. It does not act like it is going to die when I rev up in neutral and let the rpms drop, but does seem to occasionally want to shut off/lope when in gear.

    With my AFR error I took this data and paste special-mult by 50% into my VE table. Do I just keep driving and playing while logging and continuously do this until I get closer? Any help is appreciated and I am happy to atleast gotten to drive the thing and feel some good power.

    Engine is stock LM7 with exceptions of Summit 8706 stage 2 turbo cam, flat top pistons, and dual valve springs.
    Cam Specs:
    Summit Racing SUM-8706: Stage 2 Pro LS Turbo Cam. 226/230 Dur., 113+4, .600/.575 Lift, 3-bolt, 5.3, 5.7, 6.0, 6.2, 7.0, Vortec Truck, LS1 LS2 LS6 LS3 LS7 LQ4 LQ9 LS9, Each

    This motor is in my crawler with a th400 and np205 behind it with 4.56 gearing.

    Jeep field driving.hplJeep file idle updated (Speed Density).hpt

    Also seems to still want to die when put into gear.

  3. #3
    Tuning Addict 5FDP's Avatar
    Join Date
    May 2012
    Location
    Rogers, MN
    Posts
    13,533
    Try not having the open loop EQ ratio at 1.00 for all cells. That may help with the start up when cold. It's going to want a richer fuel mixture when it's cold. Have it start leaning out to 1.00 above 130 degrees.

    I think your base running airflow seems a tab high too, it's double what a stock camshaft is.


    The VE is kind of a wreck, it's super lean under throttle. Anytime you get on the gas it's in the 16's or 18's for AFR. The VE is way too low and your o2 sensors match the wideband reading of lean. Starting over with the stock VE is probably easier at this point. Do your logging, copy/paste by 50% and smooth the table after each change. There can be no spikes or dips in the 3D chart. The longer the logs the better. Short 2-5min logs won't be enough, ideally you want 15-20min logs to get the most data possible.
    2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.

    If you don't post your tune and logs when you have questions you aren't helping yourself.

  4. #4
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42
    With the start up, it does the same thing when warm also. It has to have even just .1% of throttle input to stay running on startup warm or cold.

  5. #5
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42

    New log

    Quote Originally Posted by Daniel196 View Post
    With the start up, it does the same thing when warm also. It has to have even just .1% of throttle input to stay running on startup warm or cold.
    Ok so I have made some changes and took this new log with driving around for quite a while. Looks to be lean across the board. Should I simply copy, paste special 50% and smooth or make some more drastic changes due to the values being off by quite a bit? Felt good once it hit a "powerband", but was a little laggy down low.

    Jeep 6-4.hplJeep file idle updated (Speed Density).hpt

  6. #6
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42
    I also apologize the log is not very long but it is difficult since it is in a rock crawler jeep that cant be on road and I have limited space at the moment Want to get things a little closer until I take it to a place that I can do more time extensive testing.

    Here is my take on the changes... Am I on track or way off? Jeep file idle updated (Speed Density-My attempt at VE).hpt
    Last edited by Daniel196; 06-04-2020 at 12:13 PM.

  7. #7
    Tuning Addict 5FDP's Avatar
    Join Date
    May 2012
    Location
    Rogers, MN
    Posts
    13,533
    The VE is smoother which is good.

    The open loop EQ ratio needs to be at 1.00 at operating temp, having it at .96 is going to make it leaner all over where you don't need it and then once open loop fueling is done it would try to add in during closed loop.

    Not getting long logs is going to the tough thing. If it's still lean at certain rpm section you will just have to add to the VE there on a whim. Kinda pick the section and add 5-10% worth of fuel and smooth the surrounding area's to make it clean.
    2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.

    If you don't post your tune and logs when you have questions you aren't helping yourself.

  8. #8
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42
    Quote Originally Posted by 5FDP View Post
    The VE is smoother which is good.

    The open loop EQ ratio needs to be at 1.00 at operating temp, having it at .96 is going to make it leaner all over where you don't need it and then once open loop fueling is done it would try to add in during closed loop.

    Not getting long logs is going to the tough thing. If it's still lean at certain rpm section you will just have to add to the VE there on a whim. Kinda pick the section and add 5-10% worth of fuel and smooth the surrounding area's to make it clean.

    I will be back at it on Monday. I guess once I drive around a bit more and get it all within let's say 5 percent, what is my next step? I want to learn and watch videos in my spare time but some of my best advice has been from here but sometimes seems like snail mail lol. Thanks again

  9. #9
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42

    Data and video

    Hey guys it has been quite a while and I have some new data. My scanner for some reason did not lock my layout and had to start that from scratch but got it all back I believe. I took a short log and a video to show how it runs. Is it normal with the VE not locked down for it to surge after revving up and still needing to be babied along on startup? I also have a little longer log from some field driving. I utilize paste special and 50 percent multiply for AFR changes, but it seems like the values do not get around that 3-4 percent I need to go back into closed loop. Does this simply just take more time and a lot of logs?

    Jeep file idle updated (Speed Density).hptJeep 7-15.hplJeep field driving 6-12.hpl

    The short log is simply from the startup video link below. I included by tune and a longer data log from a few weeks ago. I have made sure of no vacuum leaks since my booster was leaking and I maintain 58 psi fuel pressure on my gauge. 93 fuel being used too.

    https://youtu.be/aCiClCxL2Dk

  10. #10
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42
    Quote Originally Posted by Daniel196 View Post
    Hey guys it has been quite a while and I have some new data. My scanner for some reason did not lock my layout and had to start that from scratch but got it all back I believe. I took a short log and a video to show how it runs. Is it normal with the VE not locked down for it to surge after revving up and still needing to be babied along on startup? I also have a little longer log from some field driving. I utilize paste special and 50 percent multiply for AFR changes, but it seems like the values do not get around that 3-4 percent I need to go back into closed loop. Does this simply just take more time and a lot of logs?

    Jeep file idle updated (Speed Density).hptJeep 7-15.hplJeep field driving 6-12.hpl

    The short log is simply from the startup video link below. I included by tune and a longer data log from a few weeks ago. I have made sure of no vacuum leaks since my booster was leaking and I maintain 58 psi fuel pressure on my gauge. 93 fuel being used too.

    https://youtu.be/aCiClCxL2Dk

    Also, if I am on the right track and get the AFR within 2-4, will I then go closed loop and start timing? I am also sure I have taken all idle tuning steps, but have yet to get starts without the pedal and getting the motor to smooth out before it will idle on its own. I have watched Goat Rope Garage's tuning videos a few times, but just want to make sure I am not missing a step in the process of where I am at now.

  11. #11
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42
    Quote Originally Posted by Daniel196 View Post
    Hey guys it has been quite a while and I have some new data. My scanner for some reason did not lock my layout and had to start that from scratch but got it all back I believe. I took a short log and a video to show how it runs. Is it normal with the VE not locked down for it to surge after revving up and still needing to be babied along on startup? I also have a little longer log from some field driving. I utilize paste special and 50 percent multiply for AFR changes, but it seems like the values do not get around that 3-4 percent I need to go back into closed loop. Does this simply just take more time and a lot of logs?

    Jeep file idle updated (Speed Density).hptJeep 7-15.hplJeep field driving 6-12.hpl

    The short log is simply from the startup video link below. I included by tune and a longer data log from a few weeks ago. I have made sure of no vacuum leaks since my booster was leaking and I maintain 58 psi fuel pressure on my gauge. 93 fuel being used too.

    Going to try and get this thing tuned as much as possible this week too since I will be going to the sand dunes and would like to have something fairly stable by then.

    https://youtu.be/aCiClCxL2Dk

  12. #12
    Advanced Tuner
    Join Date
    Jun 2015
    Posts
    253
    in that video I saw you had issues with it running. You should log short and long term idle trims and idle air control position, also throttle follower. I would lower the idle timing down to like 20 degrees. More timing would make it more efficent but when you have too much timing you lose your ability to add better idle stability from adaptive idle because if you have too much idle timing if you add more it doesn't really want to increase the rpm. I think it will always just think your in park with a th400, I have a ls1 with a th400 and I believe that is what it thinks. But you could just change the timing in the idle spark and in drive spark tables to 20 degrees. You will also want to change you adaptive spark settings to something more like stock has. It takes a while to dial in the idle with a th400 because you don't have a vss. You will have to mess around quite a bit with different adaptive idle settings to get it to work good in all driving conditons. You should also let the engine get all the way up to temp and adjust the throttle blade so that the iac is just barely working so that way you have a bunch of room for adjustment.

  13. #13
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42
    Quote Originally Posted by ryan_axberg View Post
    in that video I saw you had issues with it running. You should log short and long term idle trims and idle air control position, also throttle follower. I would lower the idle timing down to like 20 degrees. More timing would make it more efficent but when you have too much timing you lose your ability to add better idle stability from adaptive idle because if you have too much idle timing if you add more it doesn't really want to increase the rpm. I think it will always just think your in park with a th400, I have a ls1 with a th400 and I believe that is what it thinks. But you could just change the timing in the idle spark and in drive spark tables to 20 degrees. You will also want to change you adaptive spark settings to something more like stock has. It takes a while to dial in the idle with a th400 because you don't have a vss. You will have to mess around quite a bit with different adaptive idle settings to get it to work good in all driving conditons. You should also let the engine get all the way up to temp and adjust the throttle blade so that the iac is just barely working so that way you have a bunch of room for adjustment.

    Thank you sir. Open to any more advice. Going to make some changes and get some logs tomorrow in preparation for the dunes in a week or two.

  14. #14
    Tuner in Training
    Join Date
    Dec 2019
    Posts
    42
    Also was my thinking above correct with the process I want to take with continuing playing with the VE tables using my afr error?