Running MAF only (VE disabled)

[scv8]

I've been running MAF only for a few days, and I perceive no disadvantages whatsoever. It is also nice not having the trims change from the morning to the afternoon. I perceive no difference in throttle response.

Am I missing something?

I'd appreciate any input.

[LSxpwrdZ]

Nope... there are alot of people that run MAF only tunes. I've gotten to where I really like a MAF sensor because it helps ALOT with weather change. But I run mine hybrid using both VE and MAF.

[MStefak]

I ran MAF only and felt a difference personally. I like hybrid myself. MAF seemed more laggy and VE only seemed like it lacked in power ( maybe because of my 7+ trims )

Either way I like my hybrid with 3500 RPM full MAF enable.

[Frost]

If you can't feel the difference in responsiveness of full MAF vs. FULL VE when both are properly tuned, you need to calibrate the butt-dyno

[MStefak]

To my understanding they should both match and feel the same no ? Since VE must be dialed in then VE is used to tune maf .. wouldnt they have to match ?

[redhardsupra]

yes, they must match, afterall they describe the same entity.
i dunno about the newer cars, but on the older cars, the SD model resulted in better throttle response. it's hard to discern on the street, but at the track, coming out of a corner, you nail the throttle at the apex and in SD it's much more immediate than MAF. it's not a big difference mind you, you really have to be watching for when the power gets applied (like when you're clipping an apex) to notice it.

[majorpayne317641]

yes, they must match, afterall they describe the same entity.
i dunno about the newer cars, but on the older cars, the SD model resulted in better throttle response. it's hard to discern on the street, but at the track, coming out of a corner, you nail the throttle at the apex and in SD it's much more immediate than MAF. it's not a big difference mind you, you really have to be watching for when the power gets applied (like when you're clipping an apex) to notice it.

I agree, drag strip is same story, I can control AFR errors much better within less than plus minus 1 percent with VE tables for all rpm's and gears.

[dimented24x7]

MAF only works well when set up properly. You will need a short ammount of enrichment during hard throttle transitions as the MAF has a transient response both due to the sensor and the method used to read in the flow. This is especially noticable with small, single plane intakes and large throttle bodies. high flow with nothing to buffer the transition. The nice thing is that MAF needs very little adjusting on most NA street motors.

[LSxpwrdZ]

I run hybrid myself as well and my MAF and VE are both dialed in to within 2% error everywhere on the table that it hits. I don't shut the VE down at a certain RPM like stock either I have it enabled to 8000rpm, which it'll never see, to make sure it stay's enabled.

[axekick]

I don't shut the VE down at a certain RPM like stock either I have it enabled to 8000rpm, which it'll never see, to make sure it stay's enabled.

I like that idea. I may try that and see how it reacts. Does anyone know if there is some disadvantage to running hybrid the whole time?

[WS6FirebirdTA00]

Why run hybrid the whole time, unless you have MAF instability issues at higher RPM?

The blend at the low end helps the transients when it is setup correctly. Yes the MAF is more consistent for fueling since it is a flow meter and measures mass flow rate. Unless you properly calibrate the VE/MAF tables and try each mode out, you can't make much from that. In some OSs the blend may make poor correction, but even then your error is going to be no worse than your repeatability. JMO.

[dsmlights]

how do you run maf all the time... I thought from factory the ls engine run hybrid???? How do I do to set it to Maf only ??

[gsegse]

Engine/Airflow/Dyanamic airflow/ set High RPM Disable to zero .

[Z06SUPERCHARGED]

Why run hybrid the whole time, unless you have MAF instability issues at higher RPM?

Would this be something to do say if the maf maxes out 12K hz or the 512 g limit say at 5K to go hybrid out to say 6500? Interesting thought but not sure how it would do or what it might change for better or worse.

[LSxpwrdZ]

Why run hybrid the whole time, unless you have MAF instability issues at higher RPM?

I do it because I'm running an 85mm truck MAF on my TA which is a 98 and it is hitting the max frequency of the table so I use the VE to help correct any errors the MAF stops picking up.

[angrygoat]

MAF only works well when set up properly. You will need a short ammount of enrichment during hard throttle transitions as the MAF has a transient response both due to the sensor and the method used to read in the flow.

My friend was having this exact issue that was causing knock retard after getting tuned by Jeremy Formato. They couldnt figure it out after pulling gobs of timing. I spent a couple days pouring over his logs and it wasnt until Marcin reminded me that when you have knock retard on the log, you have to look a few frames before it to see what happened. Thats when I noticed everytime there was knock retard, a few frames before they was a jump in MAP. Looked at the Dynamic airflow settings, and sure enough, SD was disabled. The lack of SD was causing a momentary lean spike because of the lag in the MAF. He re-enabled SD and 99% of the knock went away. He also found out his AFR was mid 15s after doing that.

[Frost]

I do it because I'm running an 85mm truck MAF on my TA which is a 98 and it is hitting the max frequency of the table so I use the VE to help correct any errors the MAF stops picking up.

The 85's top out too early. Beside that, you don't have control over blending % up top and the last MAF value will be the value that is repeatedly used. After that, PE hacking is in order whether you are blending or not. Personally, I would use a 2bar OS in a 1bar configuration to tune that car in SD.

[KLUG'S SS]

My friend was having this exact issue that was causing knock retard after getting tuned by Jeremy Formato. They couldnt figure it out after pulling gobs of timing. I spent a couple days pouring over his logs and it wasnt until Marcin reminded me that when you have knock retard on the log, you have to look a few frames before it to see what happened. Thats when I noticed everytime there was knock retard, a few frames before they was a jump in MAP. Looked at the Dynamic airflow settings, and sure enough, SD was disabled. The lack of SD was causing a momentary lean spike because of the lag in the MAF. He re-enabled SD and 99% of the knock went away. He also found out his AFR was mid 15s after doing that.

Had a very similar situation recently when tuning an 09 Impalla SS. I was working on the MAF calibration because of the addition of a K&N intake with SD disabled just for tuning purposes while tuning the MAF and was getting about 2* of knock around 1k-3k rpms, re enabled SD when I was done working on the MAF table and did a few more WOT passes and boom knock was completely gone.

[LSxpwrdZ]

The 85's top out too early. Beside that, you don't have control over blending % up top and the last MAF value will be the value that is repeatedly used. After that, PE hacking is in order whether you are blending or not. Personally, I would use a 2bar OS in a 1bar configuration to tune that car in SD.

I do actually. I switch back and forth from time to time just to see the differences. I like using the MAF while I'm daily driving cause it seems to pick up the weather changes better than the IAT and VE does. But when I race at the track I throw the 2bar OS (configured for 1bar) in the car so I know I don't run out of control/table.

[angrygoat]

Had a very similar situation recently when tuning an 09 Impalla SS. I was working on the MAF calibration because of the addition of a K&N intake with SD disabled just for tuning purposes while tuning the MAF and was getting about 2* of knock around 1k-3k rpms, re enabled SD when I was done working on the MAF table and did a few more WOT passes and boom knock was completely gone.

How did the retard of timing affect the AFR? Did that give you a fit while dialing that rpm range in?