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Old 10-14-2008, 08:27 PM   #1
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Default Tuning Fuel Economy

I'm having a difficult time tuning any off boost cruise condition for good fuel economy. Used DIY's MSPNP Spark and VE maps but tweeked on the AFR target table a bit. The map is heavy bias (obviously) on > 101kpa for boosted vehicles so this might end up being a take/give situation.

Mostly around 3500rpm and around 80kpa is where I spend a lot of time in a low to medium load cruise condition, so I tweeked teh target table at 4000rpm/70kpa to 15:1 but when you run it through megalogviewer it'll typically enrichen that general area because of how limited the AFR target table is. Do I need to go in manually and have a driver duplicate my cruise condition and adjust the target cells down a bit for a little more lean cruise condition? 3000/70kpa is 14.6:1, then the next step up is 3000/101kpa and 4000/101kpa which are 14.6:1 and 13:1 respectively. Haven't yet taken an actual numbers stab at my fuel economy instead Im just seeing a 12.6 - 13.4:1 AFR in that cruise area where I'd like it a bit lower.

How has anyone else comprimised on their map or adjusted it for optimal economy out of boost?




The VE table has been thorugh maybe 3 driving sessions so its not even remotely fine tuned yet, and obviously not tuned for any boost either.
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Old 10-14-2008, 09:46 PM   #2
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I use the target table in MLV because of the better resolution but I'm not sure that's so much of an issue. I found when I took a long trip that logging for more than an hour and driving in such a way that I make sure that i'm constantly and slowly hitting all areas of my vac gauge at different RPMs will get the AFRs almost perfect after two such logs. So if you're taking shorter logs ~20min or so it'll take more time and logs to get the numbers right.

And maybe someone else can confirm or correct me on this but I think because you're not cruising exactly at 4000 rpms and 70kpa or any other specific cell of your AFR table your AFRs are the result of interpolation between either 15:1 and 14.6:1 or 13:1.
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Old 10-14-2008, 10:58 PM   #3
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Yeah that sounds correct. I let MLV do it's thing and yeah I use the 12x12 default AFR table in it instead of the one in you MSQ. But I then tune my cruise cells manually. With your VE table open watch your AFR gauge(if you have one). If you are richer or leaner than you want to be under the present conditions note which cell is green and adjust it accordingly. Burn change. Repeat. Vary driving to cover all of the area you usually cruise in. Helps to have a passenger with you for this.
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Old 10-14-2008, 11:46 PM   #4
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Crap. I have to be missing something.. After posting this thread I did some looking through a few others and saw some people talking about the default MLV 12x12 table.. Where / How do I locate that?? The AFRBins1/2 are both from my MSQ.. Do I have an odd version of MLV?


Also I noticed the other day you can't change the Easy/medium/hard settings in the VE Analyzer anymore. I know theres an upgrade available for MLV, but I don't wanna get it because the alt menu access goes away.. Have v2.74
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Old 10-15-2008, 12:01 AM   #5
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here
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Tuning Fuel Economy-defaultafr.gif  
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Old 10-15-2008, 12:19 AM   #6
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:(
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Old 10-15-2008, 12:35 AM   #7
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Okay. Upgraded to newest version of MLV and it has the Easy/Hard dropdown box along with the 12x12 Default AFR table.. Absolutely hate that I can't access the menu with the ALT key!
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Old 10-15-2008, 12:38 AM   #8
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edit: no longer relevant.
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Old 10-15-2008, 12:45 AM   #9
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Quote:
Originally Posted by elesjuan View Post
Okay. Upgraded to newest version of MLV and it has the Easy/Hard dropdown box along with the 12x12 Default AFR table.. Absolutely hate that I can't access the menu with the ALT key!
What were you able to do before with the ALT keys in teh drop downs?

I only use CTRL O really.
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Old 10-15-2008, 02:03 AM   #10
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Well, I could press alt and go into file, view, options, calc fields, help with the arrow keys.. now it just brings up the Minimize/maximize/close menu.


Btw, Thanks. After upgrading to the newest version I now have the 12x12 Default AFR and I borrowed the one you pasted in that picture but added some fuel in key places. Ran 3 30 minute logs through it and it seems to be a lot closer to what I was looking for, but I can tell a little less power than my previous map. Seems that giving this motor a **** load of fuel makes it pull a little harder N/A.
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Old 10-15-2008, 02:58 AM   #11
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I like having the 12x12 target table in MLV but can you save it, or do you have to change it everytime
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Old 10-15-2008, 04:07 AM   #12
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it should stay
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Old 10-15-2008, 08:52 AM   #13
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Quote:
Originally Posted by turbobluemiata View Post
I like having the 12x12 target table in MLV but can you save it, or do you have to change it everytime
After you edit the table don't just X out of the window. Either hit "accept new table" or the "exit" button. That should save it. Sometimes when you upgrade it will get cleared so keep a screenshot of it handy. The export/import feature is flawed in that for me.
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Old 10-15-2008, 08:57 AM   #14
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Quote:
Originally Posted by elesjuan View Post
Well, I could press alt and go into file, view, options, calc fields, help with the arrow keys.. now it just brings up the Minimize/maximize/close menu.


Btw, Thanks. After upgrading to the newest version I now have the 12x12 Default AFR and I borrowed the one you pasted in that picture but added some fuel in key places. Ran 3 30 minute logs through it and it seems to be a lot closer to what I was looking for, but I can tell a little less power than my previous map. Seems that giving this motor a **** load of fuel makes it pull a little harder N/A.
Looking at our AFR tables(or at least the one you posted above) I'm tuning to a richer AFR than you(in boost) so why would tuning to my table have leaned your fuel map out?
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Old 10-15-2008, 09:59 AM   #15
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Well I ended up with a couple different odd issues.

First off I was questioning why I was tuning at 128kpa when I'm not boosted. Checked my engine off pressure and it was like 110kpa and I know atmospheric around here is 98kpa. Went through and checked my settings, it seems when I installed Megatune on my new laptop I forgot to go configure the correct map sensor in Configuration.

While I can't seem to locate the map I'm looking for to post it, I was observing around 12.6:1 in the mid to upper RPM range at around 90kpa. I'd really like to find that map again to be sure, but after a few logs it was running a little leaner than one of my previous maps in upper RPM ranges. Not that its a real big deal I just tweeked the upper N/A kpas for medium to high RPM a little and its made a bit of a difference.
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Old 10-15-2008, 10:17 AM   #16
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keep driving, keep using MLV, and it will eventually become a great map to use.

Rescale your fuel map and remove boosted rows:



curious to why your numbers are so freaking high....numbers above are what we used to tune a ITB miata with stock 230cc injectors on MSPNP.
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Old 10-15-2008, 01:13 PM   #17
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don't confuse them Scott. those numbers in VE table don't change based on injector size(other than for some variances in the actual flow vs rated flow). if you are changing your required fuel settings appropriately when you change injectors your VE table should remain relatively close to what it was before with just a lil tweaking.

or am i missing what you are saying completely?
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Old 10-15-2008, 01:34 PM   #18
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Quote:
Sometimes when you upgrade it will get cleared so keep a screenshot of it handy. The export/import feature is flawed in that for me.
I've had some problems with settings not saving in MLV so I keep a backup copy of the user.properties file. All settings, including the default table, are in this file.
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Old 10-15-2008, 02:06 PM   #19
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Quote:
Originally Posted by paul View Post
or am i missing what you are saying completely?

I'm curious to as why his VE numbers are so high. We started with DIYs basemap and didn't change a thing as far as req_fuel was concerned.

regardless of the figures, something is a muck, the map just doesn't look right as far as the fueling is concerned. Looks like he idles around 90%...but the rest of the map averages in the 80% zone, only getting higher with lots of load...
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Old 10-15-2008, 02:20 PM   #20
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I remember tuning with Paul one day and his numbers were really high too. Turned out that the line came off the FPR, if I'm not mistaken.
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