Lean Spike when Accelerating - 0411 Swapped Pickup

[Obsolete489]

There was an old post i had found guy had exaclty the same symptoms as i. Lean tip in, bogs hard for at lest 3 seconds and goes way lean. He ended up changing his injector timing and says his issue went away.
We also have fairly large cams, him 10?, i have 19? overlap.
We assume bc the ls1 injection style happens so early that any cam with overlap will have some sort of issue, i would believe especially swapped cars like ours being an lt1 with and ls1 pcm which have completely different designs than an ls1
You have your motor.
Even the 2002 Express van which is a SBC with an 0411 pcm has way different injector timing than an ls1.

Now could i be way off and be wasting my time, possibly. But i found a guy who had the same exact issues as i and its def worth a try.

That is pretty interesting.. sounds like the exact issue.. I will start playing with it and report back. Need to start driving this truck more often to work on this issue, and finish up the new tune.

[anniversaryss]

That is pretty interesting.. sounds like the exact issue.. I will start playing with it and report back. Need to start driving this truck more often to work on this issue, and finish up the new tune.

What are your cam specs? I could probably set somthing up for you

[Obsolete489]

What are your cam specs? I could probably set somthing up for you

218/224 @ .050, 113 lsa, 111 icl, nothing crazy, its a comp 01-415-8. I used this DWR SOIT EOIT Worksheet 041715 (2).xls spreadsheet to start, and just played with it while watching fuel trims. Also here is my current tune, I think the only thing i really messed with was the normal table, i also didn't go as far as the spreadsheet recommends with the normal table. 489 Tune - 2 bar 3-37 ifr change.hpt

[anniversaryss]

218/224 @ .050, 113 lsa, 111 icl, nothing crazy, its a comp 01-415-8. I used this DWR SOIT EOIT Worksheet 041715 (2).xls spreadsheet to start, and just played with it while watching fuel trims. Also here is my current tune, I think the only thing i really messed with was the normal table, i also didn't go as far as the spreadsheet recommends with the normal table. 489 Tune - 2 bar 3-37 ifr change.hpt

You have -5 ? overlap so it may not do much for you buy ill see what i can do after work

[Obsolete489]

You have -5 ? overlap so it may not do much for you buy ill see what i can do after work

Yeah, it does, like I said it's pretty small in the grand scheme of things, but I appreciate anything you can figure out. What I really find strange is the consistency with which the lean spike shows up, it's always north of 70 kpa and about 3 seconds into the "pull". I'll post a recent log tomorrow.