Advice for adjusting spark??? (logs & tuns & long story attached)
I went to the test-n-tune Friday night, and made 1-1/2 runs; I couldn't make any more runs because my truck was the source of major drama. The vehicle is bone-stock long-block 2003 LQ9 Silverado SS AWD, with converter/trans & Paxton Novi-1500 and 72# injectors.
Run #1, ran the truck as-is warm right off the highway and went 13.0@100 (1.84 60'), I was bummed because I was expecting at least high-12s on the initial outing. After the run I examined the log and saw:
* there was no reported KR
* WB02 leaner than I expected, but EQR was still 1.20+ and no KR so not horrible I figured
* the torque converter went into lockup in 3rd (!)
* I was only showing 9-10 degrees of timing in third gear :(
* MAP was 150+, about 8-ish pounds of boost - I was expecting 10-ish
* good ECT, ATF temps; IATs are 30+ degrees higher than I want but whacha gonna do
* I failed to see belt slippage at 5000+ RPM, this would bite me hard on the next run.
Since there was no KR I went ahead and selectively added 1-2 degrees across the "lower-right" of the high-octane spark table, raised the TCC lockup MPH for 3rd gear, and updated the PCM - that's when the drama began, the flashing process failed and left the PCM non-operative and it took over an hour to get the truck running again; that entire time I was very worried I would be leaving on a tow truck. :( Anyways that drama behind me...
Run #2 - at the end of the track the dash tells me "BATTERY NOT CHARGING", I had thrown the belt mid-run and failed to notice it until well after the traps.You find out just how good your friends are when you have to ask them to help you push your 5500-lb truck all the way back down the return lane. By this time it was very late (after 10pm) and it looked again like I was going to have to arrange a flatbed ride home; fortunately my friends came to the rescue, there are a few Autozone stores open until midnight in Dallas and one of them had the belt I needed, the rest of the night was spent driving and R&R-ing the belt and we did not get home until almost 2am. So much for testing and tuning. :(
Looking at the log for Run#2 the belt broke at 5000-RPM in 1st-gear, I think probably right at the 60-foot line. But the biggest concern on that run is the huge spike of KR. :(
I feel I have a good basic knowledge of fueling, and I see that I need to increase my VE table a few percent in the upper RPMs. But I am having a tough time learning what to do AFA strategies for adjusting spark timing, is this just trial and error at this point? I am under the impression that I will be able to run 16-18 degrees advance at WOT, but as it is now I struggle trying to even get 1/2 that.
Mr. P.
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