Only 18* of timing at WOT? 0 KR.
03-14-2016, 07:01 PM
#1
Only 18* of timing at WOT? 0 KR. I was under the impression that the LS family of motors responded well to timing. Meaning 24-28* was pretty common at WOT. I've attached a log, the config used to make the log, and my tune file. I've logged several WOT pulls and am seeing a maximum of only 18 degrees timing advance, while seeing 0 KR. I'm assuming I should have logged cylinder air mas as well, but i did not. Still, not even the low octane table calls for 18 degrees advance under 4000rpms.
Why am I only seeing a max of 18 degrees timing advance at WOT?
Thanks.
I had completely stock exhaust when I was tuned, could that why he kept timing so low?
Why am I only seeing a max of 18 degrees timing advance at WOT?
Thanks.
I had completely stock exhaust when I was tuned, could that why he kept timing so low?
03-14-2016, 07:32 PM
#2
I forgot to mention, my wideband hasnt been connected to the new exhaust.
A little back story. I was tuned with stock exhaust, from manifolds all the way back. Then I installed flowtech 1 7/8 longtubes with off road Y pipe. I picked up a GOOD amount of power. The wideband showed AFR was still good at about 12.2-12.6. But not having cats sucked on a daily driver. Its loud and smells bad.
I upgraded to Kooks 1 7/8 LTs with a catted mid pipe. I feel a flat spot in the RPM range, or a slower rise in RPMS, than before. I realize the cats impede flow, and im fine with a small sacrifice there. Just making sure everything else is on par.
I think I could have used some shitty 87 octane last week. So I topped it off with 93 and some booster.
Should I be seeing more timing advance?
A little back story. I was tuned with stock exhaust, from manifolds all the way back. Then I installed flowtech 1 7/8 longtubes with off road Y pipe. I picked up a GOOD amount of power. The wideband showed AFR was still good at about 12.2-12.6. But not having cats sucked on a daily driver. Its loud and smells bad.
I upgraded to Kooks 1 7/8 LTs with a catted mid pipe. I feel a flat spot in the RPM range, or a slower rise in RPMS, than before. I realize the cats impede flow, and im fine with a small sacrifice there. Just making sure everything else is on par.
I think I could have used some shitty 87 octane last week. So I topped it off with 93 and some booster.
Should I be seeing more timing advance?
03-14-2016, 09:50 PM
#3
I should also add, that the original tune file is from a 2003 4.8 truck ecm. I know the trucks use a bunch of different metrics to add and pull timing based on various parameters. How can I adjust those parameters to better suite my 5.7? The logs dont lie, 18* is the max total timing at wot. Thats gotta be costing me some power.
03-15-2016, 08:03 AM
#7
Just look at your High Octane and Low Octane timing tables. They are set for a max of 19°. The AFR Correction table should add 2° if you get into PE but your IAT correction is taking that 2° back out since the intake air temp is mid 90s. The ECM is doing just what the tune is calling for. If you want more timing, add it to the high and low octane tables. In you tune they are both the same values.
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03-15-2016, 08:49 AM
#8
Just look at your High Octane and Low Octane timing tables. They are set for a max of 19°. The AFR Correction table should add 2° if you get into PE but your IAT correction is taking that 2° back out since the intake air temp is mid 90s. The ECM is doing just what the tune is calling for. If you want more timing, add it to the high and low octane tables. In you tune they are both the same values.
Isn't it very common for an ls1 to run 24-28* of timing? Why the hell did the tuner not bump it up? maybe he thought I was gonna be towing with the truck...?
Last edited by Justhereforinfo; 03-15-2016 at 08:57 AM.