Who's running Open Loop with a MAF?
Thread Starter
Joined: Nov 2001
Posts: 8,246
Likes: 34
From: Victoria, TX
Who's running Open Loop with a MAF? I am. After the problems with my narrow-band O2 sensors, I got my speed density tune really good with the wideband. I even leaned out the cruising cells so I'm closer to 15.0:1 A/F ratio so I can pick up a little fuel economy.
Since I've been wanting to run a dry shot again, I went ahead and rescaled my MAF and now I'm running 100% open loop, but with a MAF. Am I one of hundreds doing this or am I alone?
Since I've been wanting to run a dry shot again, I went ahead and rescaled my MAF and now I'm running 100% open loop, but with a MAF. Am I one of hundreds doing this or am I alone?
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
TECH Regular
Joined: Jul 2005
Posts: 423
Likes: 0
From: Lombard,IL
i didnt get to choose, but when i brought it to speed inc to get a basic tune, they put the car on open loop w/ maf. i herd havin ur car on open loop does not make the car ever run the same again. maybe speed inc can chime in on this one. i plan on tuning my car through speed density and leaving the pcm on closed loop
I have two cars running in this method. narrowband o2's are not pratical in all situations. I nailed down the ve tables then maf. They run great with OL and maf. For awhile it seemed I was the only one doing it too.
Thread Starter
Joined: Nov 2001
Posts: 8,246
Likes: 34
From: Victoria, TX
I really like the advantage of having kick-*** VE tables to reference and also the ability to run a form of lean cruise. The MAF just gives me a little more flexibility and also enables me to run the sneaky dry shot. I knew I was running these big injectors for a reason, haha.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
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I've not dealt with MAF for a long time now, but smog time is here again and I'm trying to dial it in, and I'm having major issues--which is funny considering I invented MAF calibration process.
My main reason for staying away from it is that a VE table is just so much more descriptive: you have pressure and engine speed, two major influences. this way you know exactly the conditions that are going on in the engine. With MAF all I got is like 6000Hz--what does that mean? But at the same time, if you hit a 5000rpm/70kPa cell on SD, it's also gonna just calculated to some airflow number, still not yielding any extra information like is it in the process of accelerating or decelerating, and so on.
The good part of SD that it's easy no nail the whole range. MAF is very easy, precise and consistant under more load, but at idle and right off idle, it's very messy and unprecise, making tuning difficult. that's why probably GM decided to give us a hybrid maf/sd mode for the low rpm/light load situations.
My main reason for staying away from it is that a VE table is just so much more descriptive: you have pressure and engine speed, two major influences. this way you know exactly the conditions that are going on in the engine. With MAF all I got is like 6000Hz--what does that mean? But at the same time, if you hit a 5000rpm/70kPa cell on SD, it's also gonna just calculated to some airflow number, still not yielding any extra information like is it in the process of accelerating or decelerating, and so on.
The good part of SD that it's easy no nail the whole range. MAF is very easy, precise and consistant under more load, but at idle and right off idle, it's very messy and unprecise, making tuning difficult. that's why probably GM decided to give us a hybrid maf/sd mode for the low rpm/light load situations.
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TECH Addict
Joined: Jul 2002
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Right now I'm Open Loop SD. But I've spent most of my time Open Loop though the MAF.
I haven't been closed loop since the early NoGo-VE tuning days. Since the july 2003 thread -> "Changed VE Table now i have a slight Hesitation!".
I haven't been closed loop since the early NoGo-VE tuning days. Since the july 2003 thread -> "Changed VE Table now i have a slight Hesitation!".
Originally Posted by Patrick G
I really like the advantage of having kick-*** VE tables to reference and also the ability to run a form of lean cruise. The MAF just gives me a little more flexibility and also enables me to run the sneaky dry shot. I knew I was running these big injectors for a reason, haha.
Originally Posted by V6 Bird
you can run the dry kit without the maf as well.
Originally Posted by slow
Just curious when did you invent the MAF calibration process?
Ryan
Ryan
Originally Posted by Patrick G
I am. After the problems with my narrow-band O2 sensors, I got my speed density tune really good with the wideband. I even leaned out the cruising cells so I'm closer to 15.0:1 A/F ratio so I can pick up a little fuel economy.
Since I've been wanting to run a dry shot again, I went ahead and rescaled my MAF and now I'm running 100% open loop, but with a MAF. Am I one of hundreds doing this or am I alone?
Since I've been wanting to run a dry shot again, I went ahead and rescaled my MAF and now I'm running 100% open loop, but with a MAF. Am I one of hundreds doing this or am I alone?
if you wanted closed loop and a leaner mixture u could also adjust the o2 switchpoints. i run about 15.5:1 im still working on getting the o2s to move a lil better at idle..........
Originally Posted by slow
Just curious when did you invent the MAF calibration process?
Ryan
Ryan
The correct way IMO is to use a AFR% error. This was thought of by HumpinSS and tested by myself. I don't uses spreadsheets anymore when all is available in EFILive. 
I've never tried doing a MAF tune...I've been SD since I started tuning. It ran so well, I figured why change? I did, however, have to switch to open loop when my O2 sensors took a dump, and I haven't looked back. I love how stable it is, and I monitor the A/F ratio with my wideband full time with my XD-16 gauge. It is always right where I want it.
That being said, I now have a full custom intake setup, and the IAT sensor isn't even close to the engine anymore, so I don't have the lean restart issues I used to have. It works great for me, and the car runs strong (for what it is).
That being said, I now have a full custom intake setup, and the IAT sensor isn't even close to the engine anymore, so I don't have the lean restart issues I used to have. It works great for me, and the car runs strong (for what it is).
Originally Posted by ninobrn99
Chad, what do you do for cold and warm starts with the MAF? ive tried it, but ive had issues with it hunting and searching for idle 
(not trying to hijack Pat) 
(not trying to hijack Pat)