1966427

Looking for some feedback on MAF only tuning a LS3. The car is my daily driver and I'd like to know if there are any issues tuning this way. If the maf starts to fail is there a fail safe to protect engine?

schpenxel

MAF only can work. Generally SD is smoother which is more noticeable on setups with large cams or something with a lot of turbulence.

SD model is still used for transients (quick changes) so you really should still at least have the VE table in the ballpark.

Factory uses both. No reason you can't do the same other than not wanting to spend the time to do it.

1966427

Is tuning both sides as simple as disabling maf, tuning sd, then disabling sd and tuning maf? I read bluetorps article(http://www.camaro5.com/forums/showthread.php?t=196696) on the camaro5 forum describing this process. Should I still follow that with the exception of using hp tuners virtual ve table instead of his software?

schpenxel

I can't read the thread right now but in general, yes

1966427

Ok, thanks for your time.

Unreal

Pros

Easy. Quick.

Cons.

​​​​​​It's the quick easy half *** way to tune. Maf doesn't like reverb or quick transients so fueling will never be as good as it could be.

DSteck

You don't have to be in pure SD to calibrate the VE model. It requires some math, but otherwise fairly straight forward. I do it all the time. I tend to tune cars and leave them in blended mode. I do disable predictive modeling though.

1966427

Where can one find said math?

schpenxel

hptuners forum, it has been posted there

or google GMVE, figure out the units and work backwards from there

1966427

Cool, thanks guys. Can maf be tuned w/o disabling sd as well?

1966427

I've read to get fuel correct before playing with timing. Is that correct?

schpenxel

Depends on setup, but basically I'd say make spark safe, get fueling correct, play with spark, re-adjust fueling as necessary along the way

1966427

I'm adding ls7 exhaust to my GS next week but is otherwise stock. I just want to learn as much as I can before I do a cam, and CAI

schpenxel

Yeah for that not a lot to worry about as far as destroying something goes IMO, should be fine

rio95

Why are you not wanting to disable maf for ve tuning and visa versa? That's the way every book I've ever read teaches ya. Works great for me. Why make it more complicated than it needs to be?

Unreal

Because it isn't more complicated. It is quicker/easier. Just set up formulas/math and then you don't have to mess with 2 different tune sessions, one with maf on and one with it off.

1966427

It's not that I dont want to disable maf to tune ve. I was talking about pros and cons of tuning maf only. Disabling sd and running the car maf only.

Unreal

I was responding to rio.

schpenxel

Books are showing the simple way, not necessarily the fastest/smartest way. Either way can work.

rio95

Yeah I know that was your main question. My Z06 seems to run smoother with blended. Also, I figured GM does it for a reason so probably best to maintain it.