Tuning MAF at high RPM

[gtstorey]

OP, did you get an affirmative answer on this? I'm tuning my 5.3 truck right now and in the same boat. My thought is to tune VE up until 4k bc I plan on running the Maf still.

I dialed in the maf recording afr % error with a wideband while cruising on the highway trying to achieve steady state.

What is the technique to tune WOT with the maf?

Full throttle and record the afr% error? Multiply x %?

OP hasn't posted since 2010.

[LSROVER]

OP hasn't posted since 2010.

Ok, can you help?

[blindsquirrel]

Ok, can you help?

Re-read the entire thread until you understand it well enough to formulate a good, answerable question. "Hey OP did you ever solve this?" is just a shit way to get information.

Tune the VE. All of it. All of it it's possible to hit while logging, anyway. Then tune MAF. All of it. Looking for shortcuts might seem harmless but it usually comes back and bites you later.

[LSROVER]

I read every single post.

There's no clarification on the method of tuning MAF TABLE for WOT. Do you ease into the gas to reach the upper hrtz cells or do you go WOT to redline? Mixture of both?

[eXo3901]

Start by easing into it.

[LSROVER]

Start by easing into it.

Thanks. Makes sense as to keep airflow smooth as possible.

Do you guys prefer to use the afr error % in the scanner or manually change the hertz to get desired afr for maf?

[PRS]

Thanks. Makes sense as to keep airflow smooth as possible.

Do you guys prefer to use the afr error % in the scanner or manually change the hertz to get desired afr for maf?

I use the AFR error % to make adjustments and then I look at the whole MAF curve to smooth out the cells I didn't capture data for and manually go in and scale.

[Tunercharged]

For my WOT MAF tuning I use PE and make a run making sure not too lean with my wideband. Then I use a filter on the data so my MAF table in the scanner only holds data for the part of the data I want to change, then paste special percent half the whole thing. Using a filter to clear the other parts of the table than the ones I am trying to change makes it easier for me to just concentrate on those parts. I?ll use a filter that says delivered torque above 375 and throttle above 60 percent, something like that for a scanner chart filter.

[Matt Vardaman]

OP, did you get an affirmative answer on this? I'm tuning my 5.3 truck right now and in the same boat. My thought is to tune VE up until 4k bc I plan on running the Maf still.

I dialed in the maf recording afr % error with a wideband while cruising on the highway trying to achieve steady state.

What is the technique to tune WOT with the maf?

Full throttle and record the afr% error? Multiply x % into the VE table?

You tune VE and MAF the same. From idle to full throttle with a wideband with % error graph. Leave PE on with a wideband, because it affects commanded afr and you are trying to hit commanded. You commented on a post from 2006 when these guys were figuring things out. It does not matter which one you tune first.

[LSROVER]

Thanks for the response. I've watched and read many tutorials but none of them actually highlight the process of tuning WOT.

One more question: if I'm running a hybrid setup with a maf I assume I don't really need to tune VE wot at 4000+ rpm. Is that assumption correct?

[Matt Vardaman]

Thanks for the response. I've watched and read many tutorials but none of them actually highlight the process of tuning WOT.

One more question: if I'm running a hybrid setup with a maf I assume I don't really need to tune VE wot at 4000+ rpm. Is that assumption correct?

You don't "Have to" if you are leaving the stock setting of using filtered Maf above 4000rpm. I personally tuned my maf curve first. I was ocd about tuning my daily early on, so I spent my drives to work tuning the Maf for a week under all kinds of throttle. I started off only tuning the VE table for idle and steady state cruise. More recently I have spent more time on the VE table and have it tuned from idle to Wot. The truck idles better running on VE only, but most of the time I run it with the stock settings in the dynamic airflow tab. I've tuned the truck again after each modification (Injectors, flex fuel, longtubes, etc) Good luck tuning!

[LSROVER]

You don't "Have to" if you are leaving the stock setting of using filtered Maf above 4000rpm. I personally tuned my maf curve first. I was ocd about tuning my daily early on, so I spent my drives to work tuning the Maf for a week under all kinds of throttle. I started off only tuning the VE table for idle and steady state cruise. More recently I have spent more time on the VE table and have it tuned from idle to Wot. The truck idles better running on VE only, but most of the time I run it with the stock settings in the dynamic airflow tab. I've tuned the truck again after each modification (Injectors, flex fuel, longtubes, etc) Good luck tuning!

Thanks for your input. It took a lot of reading and watching videos but I finally understand what I'm doing.

I purchased a mail order tune which I regret but that was the only option at the time. It was merely good enough to start up and drive to a tuner. The IFR table was jacked and the VE table was essentially stock (I have a 5.3 with btr truck Norris cam, LS3 injectors, custom intake for my swap). I'm estactic that I don't need to rely on a tuner when I need to make adjustments.

At this point I've spent my morning drives dialing in the VE table in similar weather conditions. I have my afr errors within 3 percent rich right now. Truck drives well. I'm going to work on the maf tuning next week at steady state highway cruising. My plan after that is to enable stock dynamic settings to see how it behaves then tackle the WOT tuning with the MAF.

My swap is in a Land Rover. If I had to do it all over again I would have left the engine stock but it's pretty cool learning how to tune the setup.

[Matt Vardaman]

I used a mailorder tuner the first time myself too. It was a waste of money. It may be good in some situations, but not for me. I bought a Summit Pro Ls truck cam when they new and were cheaper. Now I wish I had bought a camshaft with more duration. The truck runs good on pump E85 which is 64% every time at the local gas station. I like tuning and my full throttle fueling error is within 2-3% like the steady state. I go to the drag strip every other month and it's safe to dial in the wot tuning there. I leave the truck in closed loop at the track on only adjust the area of the map/maf that are at 100% tps, because the pcm switches to open loop accel/decel when in Power Enrichment.