I did an engine swap into my Jeep JK using a 5.3 out of a police Tahoe. I deleted the DOD and put a 6.2 cam that goes with their kit. I also had to put an LT1 intake and throttle body for clearance reasons. I updated the TB and intake sizes in the tune and have done a few MAF and VE tune runs to get it semi close.
It idles great and I've driven it for over a year but it needs some help. I feel like it's pulling timing when I get on the gas beyond normal acceleration and I'm hoping it's just because the timing is off from. I've tried to pull values from a bunch of different 6.2 tunes but none of those seemed to help. I could really use some help getting this thing dialed.
I'll attach my current tune, a log file from a longer drive a couple weeks ago and one from today that's just idle. I did just change my channels to use the Ready Racing channels today so the longer log is missing some things that are probably helpful but my biggest concern is all the knock.
You need to increase the polling rate of the log parameters. Your log shows a 2 hour drive yet many of the critical cells only have a couple hits. For instance, when I look at fuel trims, I want no fewer than 50 cell hits for me to care about a given cell. There's a whole area in your 2 hour drive that there's only 1 or 2 hits. Are you logging via BT? If so, that's been the issue in the past. Gotta plug into the OBD port.
Looking at the timing, that appears way off (high), particularly in the 1800-2500rpm range. I think you're getting spark knock.
Which LT1 intake do you have? Looking at a stock LT1 Vette file, your intake volume is about 700 cubic cm more than the Vette file. I'm assuming you pulled a value from a 6.2 truck? Just making sure
I wouldn't worry about pulling timing values and tables from other tunes. I'd increase the polling rate, and then adjust the tune based on what you see in your logs.
Is there a difference between the polling interval when connected via USB and standalone? Looking a the channel configs, everything is set to 0ms. Log-0174 was done by pushing the button.
I'm sure my timing is way off as well. I guess I should get it in the ballpark first, tune MAF and VE and then dial timing in.
LT1 is for an 18 Vette. I checked my original tune from the Tahoe with the truck intake and it was 728cc less than what I have. I must have added instead of subtracted when I made that change.
Logging via BT is slower. I always log connected to my laptop. Looking at it another way, you have a 2 hour and 26 min log and it's 3Mb. I have a 22 min log and it's 7.8Mb
I've never seen anything set to 0ms. The fastest it should go is 10ms. "0ms" isn't even one of the choices. FWIW, I log stuff like fuel trims at 50ms.
I've attached one of my random logs used to work on my 416 build so you can see what I'm talking about regarding the amount of data.
FWIW, I looked at a stock 2019 Corvette LT1 tune and the intake volume is 13,520 cm3
I updated the manifold volume, set any of the channels that were being used in the graphs to 50ms and logged via the laptop. This one looks better. Big thing I'm trying to figure out is why it doesn't feel like it has any power at WOT.
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