Help appreciated with a not-so-good tune

[Joyridin']

I had a tune done for my car and am having some issues. I had Greg Huggins tune my last 2 cars and after a lot of work, they both came out excellent. Unfortunately, he is no longer doing that type of work as he has retired and moved on.

The engine is a LS3 based 427 with BTR cam, headers, FAST intake, and 103mm TB. Nothing overly special in the big picture. I had a tune done and it idles fine and runs down the road fine, but when you give it gas at any RPM, it stumbles, then catches again and takes off. It does not seem to be temperature sensitive. The tuner keeps saying it is mechanical, but it has a 450 lph pump, 550cc injectors, and complete return style fuel system running at 60 psi. The car originally had a supercharger, so it has twin 450 lph pumps and I can keep both of them running and it still stumbles. There are no errors being shown in the scan.

Any ideas where to start? I tried messing with a few things, but they set it up as a speed density tune and I am not overly familiar with some of the numbers. Any help would be appreciated. It is kind of hard to drive as the stumble/hesitation can get a bit violent at times. The last tune they did and the last log is attached. Thanks for any help.

[2xLS1]

Greg is not tuning anymore? That is surprising to hear.

[Joyridin']

Greg is not tuning anymore? That is surprising to hear.

He moved to Japan or New Zealand and called it a day. He hasn't been on here since February and he moved in March.

[2xLS1]

IMO it's not the easiest business to be in with all the headaches that come along with it.

[edcmat-l1]

Could be misfires. Kinda looks like it in the log. Need to check your plugs and wires good. Most of the time it's due to a plug wire or wires not snapped on the plug or coil good enough. See it almost daily.

[abc]

Can you point to the time stamp when you feel the problem? If not, the next time you log it and feel the problem, tap the space bar. When you tap the space bar it will stop the log and save it, you will know the issue is represented at the end of the log. You then can tap the space bar again to start a new log.

There is at least one event that is showing lean and excessive knock retard when throttle is applied. 6:15.045

[Joyridin']

Here is an earlier log. If you look between 7:43 to 7:54, you will see it happen. There are many other spots, but it is really clear. The car is going lean. You can watch the AFR on the AEM gauge go to 17:1 or even as high as 20:1.

[abc]

I don't know enough about the Gen 4 to know why there is no VVE table for yours. With that being said, looks like you need to add fuel in your problem area. It may take figuring out the VVE issue, adding PE sooner, or adjusting the transient fueling.

If your WBO2 is correct, it is likely this is your problem and it just needs more fuel in your problem area.

Based on how lean it is getting, I can't rule out a secondary ignition miss through a keyboard based on how the NBO2's trace looks. Do you know what a secondary ignition miss feels like? Do you ever feel the issue and not see the excessive lean spot corresponding with it? I would do a complete physical on the secondary ignition system, if no problem found, I would add some fuel in the problem area and re-test.

[Cringer]

He moved to Japan or New Zealand and called it a day. He hasn't been on here since February and he moved in March.

Wow...I was wondering what happened to Greg. His exit is a loss to the tuning community.

[edcmat-l1]

Wow...I was wondering what happened to Greg. His exit is a loss to the tuning community.

Yeah it is he was a sharp knife. Seems he just quietly went away.

Wish he woulda took me with him if he went to NZ!!! LOL

[STL_G8GT]

Yes it's tough - I've got a mostly complete tune from him and he just went dark. I think it'll be fine, but he's gone gone. I emailed him a couple times, cordially, and no response. No forewarning. At least now I know what happened, I was afraid something terrible had transpired.

[lewma]

tap the space bar. When you tap the space bar it will stop the log and save it, you will know the issue is represented at the end of the log. You then can tap the space bar again to start a new log

I never knew that. That makes things a whole lot easier!

[biholliday]

my car did the same after the cam install. the solution was to apply the 2 bar OS which enabled the vve table in the edit menu. with the vve table enabled you can then set up your scanner for tuning that table. if you look up silversurfer77 on YT his videos are a must if you try to dial in your tune. i have managed to tune my own car good enough for my wife to daily which is saying i successfully tuned my LS3 with HPtuners. my car is a 2014 ss sedan with a BTR stage 2 cam 2 inch headers scat pack mufflers wishing i had the money for some Borla or Corsas. my tune is not maf or speed density only it is blended as it was when i started. be prepared to spend some time if you do it yourself.

[Joyridin']

my car did the same after the cam install. the solution was to apply the 2 bar OS which enabled the vve table in the edit menu. with the vve table enabled you can then set up your scanner for tuning that table. if you look up silversurfer77 on YT his videos are a must if you try to dial in your tune. i have managed to tune my own car good enough for my wife to daily which is saying i successfully tuned my LS3 with HPtuners. my car is a 2014 ss sedan with a BTR stage 2 cam 2 inch headers scat pack mufflers wishing i had the money for some Borla or Corsas. my tune is not maf or speed density only it is blended as it was when i started. be prepared to spend some time if you do it yourself.

I will check into that. This is a GMPP E67 computer, so there are quite a few things that are different than a standard E67. I know we tried a few things when the car was supercharged and the computer didn't like a few of them that seemed to work fine on a standard E67.

I have it running decent now. It doesn't hesitate anymore, which was dangerous.

[GHuggins]

I was going into something else, but things fell through. Still tuning albeit health took a serious hit this last month. Getting better right now and still tuning... I will say if anyone out there right now has investments, nothing is off limits for the crooks and our new government doesn't give two flips if they're stolen, so keep an eye on things.

[Cringer]

I was going into something else, but things fell through. Still tuning albeit health took a serious hit this last month. Getting better right now and still tuning... I will say if anyone out there right now has investments, nothing is off limits for the crooks and our new government doesn't give two flips if they're stolen, so keep an eye on things.

Sorry to hear about your struggles ol' pal. Hopefully things get sorted out across the board.

[STL_G8GT]

I was going into something else, but things fell through. Still tuning albeit health took a serious hit this last month. Getting better right now and still tuning... I will say if anyone out there right now has investments, nothing is off limits for the crooks and our new government doesn't give two flips if they're stolen, so keep an eye on things.

Good to see you around Greg!!! Glad your health is coming back around!