Thread: Eliminating KR - I think I see the problem?

Hey guys, not new to these cars at all, but definitely new to tuning. The last L67 car I played with at all was my '98 GS years ago (3.4" pulley, headers, 3.29s, etc), and it was just a car I got very lucky with: the DHP 1.5 BIN worked flawlessly on that car and I never saw anything beyond tiny blips of KR on hot days and, as far as I know, that car still runs great for the current owner.

Now I'm back with another car, an '01 GS, and I'm getting my feet wet into modding again. Last weekend I did a Gen V swap, along with some other stuff. So for now the mod list is:

• 3.6" pulley on Gen V
• Front and rear Powerlogs
• 3" downpipe
• 3" catback
• Intake
• AL104s

I'm noticing that I'm getting some sustained KR near the end of each gear, along with some blips here and there. At first, I attributed it to the DHP tune, so I went back to stock and started over. Generally, the KR doesn't exceed ~2.8 degrees or so, but on a recent scan I did see one blip of 4.2 degrees which really scared me. I started going through Jerry's Tuning Notebook as a guide and wasted a lot of time on a VE tune until I got back on here and read again that it's probably not worth it. So I did some scans and used Eddie's table tool to try and clean up the MAF tune a couple of times, but to no real difference. As of now, the PCM is stock minus the changes that Jerry suggested for torque management, shifts, etc along with the MAF and VE tables slightly tweaked. I have included the BIN file currently on the car.

Looking at the scans, it seems that my O2 readings are below where they should be, only in the high 800s. This would indicate I'm leaning out, right? Is this too aggressive of spark advance or simply not providing enough fuel? I'm seeing positive LTFTs so I'd think it's too lean in the tune..

I REALLY wish I would have had a more recent scan of the car unmodded, but the last time I scanned it was probably in May '16 when I got an AVT box and dumped DHP 1.5 on it. It had no appreciable KR then, but that was also with good summer fuel down in GA, not to mention being totally stock, right down to the U-bend. I don't know if a combination of the terrible winter-grade 93 octane and the ~55 degree weather is making matters worse here.

I'm in the middle of reading through webracin's tuning guide that Scotty linked to in another thread, there's just a lot to take in right off the hop.

Scan 1: http://superchargedv6.com/tuning/9Mar2017-Scan1.csv
Scan 2: http://superchargedv6.com/tuning/9Mar2017-Scan2.csv
BIN: http://superchargedv6.com/tuning/MAFTune2.bin

did you do the cat kill in tiny tuner? that could be hurting ya.

whats your wot timing set at in the bin? might have to pull it back some, when you have kr thats not going away the maf and the o2 readings become off.

Without a wideband, you really have no idea where your wot fueling is. It could be 13:1 or 9:1.

what down pipe you get? if its got a hi flow cat you need to delete the rear o2 from the bin, and then delete its codes and the cat code.

It's super easy to shut that test off.

that dp will over fuel aka fail its cat test for sure in the 01-03 cars.


looks like a dhp timing file. its one higher then stock wot.

you need to copy every folder over, not just this or that one, they all have changes.

the only things i dont swap over if theres a year change is the diagnostic folders, where you delete codes, cause they are not the same, and your maf hertz part of the maf file. what ever the top file is in the maf folder keep that one stock for your car. you can tune it later if you need to.

and make sure the injector file is stock too, unless your changing them. some of them tuned bins have injectors swaps in them, and then also double check the rpm and mph shifts in the tranny folder, cause those might be to high for you.

i gave up on the table modifier thing. i really dont think it makes a large enough swing at things, why it takes 5 to 10 scans and blah blah blah. waste of gas.

if you got your old trany file and it had stock ish shift points, use it. dont think id shift it at 5800 on stock valve springs, cause 5800 ends up really being 6000 or 6100.

your in the right folder, leave the other two alone. bottom 3 rows are your wot timing in gfs.

being its still cool out, the cold air keeps the kr down, come summer you might have to play tuner again if you see kr.

Hard to say.

If you still don't know your true AFR, it's still a guessing game.