C6 Z06 MAF and SD Tuning Help

[rio95]

***EDITED (I was asking too many questions at once lol)

My setup consists of the following:

2007 z06
WCCH stage 2 heads (11.8-12.0:1 CR)
Hell widow cam
Halltech 107R intake
Stock exhaust and fuel system
E10 fuel

I'm retuning my car from scratch and plan to start calibrating the MAF and then moving on to the VE table. My goal is to improve drivability (bucking and hot start issues)and try to get rid of some knock I'm getting at WOT in upper RPMs and during transient conditions.

After I put the car in open loop and adjusting all the fuel tables to ensure I'm not trying to hit a moving target, do I put 1 in for the higher temps of the open loop EQ ratio table or the same thing I put in the PE table (i.e. 1.18)? Everything I've read says 1, except for the Master EFI Tuning book by Dan Maslic. So why the inconsistency?

Also, for tuning the MAF I know I need the put the car in pure MAF mode. I plan on doing this by inputting 2rpm in dynamic airflow high RPM disable and 1rpm in the re-enable box. Is there anything else I need to do for this?

During VE tuning, I know I should disable the MAF. I need confirmation on how to do that. Do I need to do something in the DTC tab and/or unplug the MAF? Or perhaps put high values in the dynamic airflow boxes? I know how to do this on LS1's, but I see it's different for E38's.

The attached image is all I need to do to put the car in open loop, right?

Any help would be greatly appreciated.

[SultanHassanMasTuning]

how the stock tune is setup is somewhat of a Hybrid between both MAF and SD, you can either bypass the SD or go pure MAF. I have tuned several heavy combos using MAF only with success.

some cams just have that nature of slight bucking cruising if your in the 1500rpm range or so down the highway.

[rio95]

how the stock tune is setup is somewhat of a Hybrid between both MAF and SD, you can either bypass the SD or go pure MAF. I have tuned several heavy combos using MAF only with success.

some cams just have that nature of slight bucking cruising if your in the 1500rpm range or so down the highway.

Yeah I'm aware that the stock setup is a hybrid. I'm planning on trying to keep it that way too.

I don't expect to get rid of all the bucking and that's fine. Gotta take the good with the bad! With that being said, I'm confident the bucking can be reduced, because nothing was done to improve it other than remapping the MAF. The drivability is exactly the same as it was when I first got my build done and drove on the stock tune.

[Michael_D]

My personal experience tuning my C6Z, is that MAF sucks under about 3000 rpm if you have a lumpy cam and you absolutely need to dial in VE, or VVE if you intend to keep the OE operating system.

The first step, and go no further till you take it, is to make damn sure your injector data is correct.

Next step is to make sure you have no vacuum leaks. Then you need to figure out if you want to calibrate fueling in OL with a wide band, or CL and fuel trims. WOT tuning requires a wide band, obviously, as the ECM doesn't reference the O2 sensors when in OL. When I make a change to my engine that will require a re-cal, I will calibrate in OL and use a wide band, then I move to the fuel trims, because the ECM will reference the O2 sensors when in closed loop. I do not subscribe to the train of thought that some have, which is to just leave the ECM in OL. I like to start with VE, and get the AFR error under 2% in all cells, then I'll move to MAF. Oh, and make sure you let the ECM get over its hangover from a new flash for about 10 minute before logging data. For reasons unknown, it goes rich, then settles down after a while. There's a few threads on that topic worth reading. Sure wish I would have known about that when I first started screwing with my car....

The tables you need to modify are many. It would take a lot of writing to tell you what you need to do. I suggest you buy another book, read up a bit, and also download a few on-line tuning guides. Then come back and ask more pointed questions. Nobody on this site will spoon feed you basic stuff. This is a pretty good beginner's book that will help you out some.
http://www.lasotaracing.com/MOHPGMTuningGuide.html

It's not perfect, but a good start.

[Maxspeed96ct]

On my e40 ls2 I had better luck with my cruise/ part throttle ve tunning using the CL fuel trims. STFT was all I used, I spent allot of time trying to get it with the wide band but could no get it close enough. I used the wideband for / OL of course, but for part throttle,idle, and cruise cruise tuning with the STFT worked best for me.

[rio95]

On my e40 ls2 I had better luck with my cruise/ part throttle ve tunning using the CL fuel trims. STFT was all I used, I spent allot of time trying to get it with the wide band but could no get it close enough. I used the wideband for / OL of course, but for part throttle,idle, and cruise cruise tuning with the STFT worked best for me.

Interesting. I'll keep that in mind if I run into issues.