Hi, I had a question on deleting MAF sensor and only using the MAP sensor. My friend is running his motor this way.
He said that it is easier for the tuner to tune computer.
Is it better to do it this way or should I keep the MAF?

 

Keep the MAF.

And tune both MAF and VE (separately).

 

what your talking about is a "speed density" tune (1 bar) and will cost double the credits to do at least with HP tuners I dont know how efi live does it or if they offer it.

Some prefer it for ease of tuning others stay with the maf sensor and do as suggested above maf & ve tune.

where you said "He said that it is easier for the tuner to tune" is it safe to assume you will not be tuning this yourself and you will likely be using the guy that tuned your friends car ? if yes then sometimes if your local tuning options are limited it may be in your best interest to play to your tuners strength - if he prefers speed density then he has likely recommended a lot of them and therefore has more experience with them and if your only other option is a remote tune you will have a choice to make.

another question to ask is if he does open loop speed density eliminating input from factory o2 sensors in addition to the maf and doing the tune based on wideband tuning and with the elimination of the maf and 02 sensor input it basically locks the fueling as pre-set , one of my z's was done this way by the previous owner and works well , I always did maf(ve table zero'ed out) and ve (maf disconnected or shut off in tune) with my cars but this car has run well for me for 4 years and in talking with him he knows more about tuning than I do so I have left it alone until I need to touch it. I am not saying its better just trying to help you know whats out there and what questions to ask.

 

a sd tune costs more because it takes more time to do it . I have it done on my car and it needed it . Why do you think your car needs it . Boost, large cam ??

 

A lot of guys like SD for the throttle response you gain from it. With the MAF in place it is actually pretty easy to tune, but really, the VE still needs to be programmed properly for transition fuel delivery. Your PCM/ECM will use a combo of MAF and MAP when not in PE mode and for transition fuel conditions. In PE it will solely use the MAF. The combo, using MAF and MAP, just feels better imo, starts better, handles changes in elevation better, nets better fuel mileage and is just a smoother feel overall. If your a full out racer I say go full SD but if your daily driver sees the track once in a while each year then have a VE/MAF tune applied to the car. Now, there is a point where this gets kinda funky and your tuner needs to know where to draw the line. When you get into larger cams, heads and headers idle cannot be tuned keeping trims active. The narrow bands by sheer design are completely useless and you have to have someone that knows exactly what they are into and can command PE at idle, then properly tune it for that. Have MAF and trims active for off idle(cruise) regions of the tune and then run full MAF when in PE. The better the VE is tuned the better the car is going to handle transitions using the MAF and you can really feel the difference when this is done right. I'd like to add, if you go SD, make dam sure that IAT sensor is properly calibrated. It is essential for a SD tune to function properly. A MAP sensor does not meter air and relies on pressure and temp to calculate its final fuel delivery. It is important for either system to have the IAT calibrated but you do seem to get a little more leeway with the MAF over the MAP in that respect. I agree with joecar's comment there myself

 

EFILive allows SD...


for anyone curious reading along:

EFILive allows tune to be edited for any of the four modes: OLSD, CLSD, OLMAF, CLMAF.

EFILive also offers a few COS's depending on GM OS id (extra license "credits" not required)... these also allow running any of the four modes; and one COS (COS5) also allows Alpha-N (VE based on TP rather than MAP).