mefi tuning question for experts
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There's thousands of other ways to make it better but you have to get far deeper into the software. Without being able to program on the fly, trial and error takes forever.
Dustin
That is one big downfall of mefi burn also no slew I use that alot. MEFI is not fast or dfi, the full mefi hud software
has way more adjustment than the aftermarkets, way harder without a good base cal to start with.
How you like my post count Dustin?
Mark
Dustin
That is one big downfall of mefi burn also no slew I use that alot. MEFI is not fast or dfi, the full mefi hud software
has way more adjustment than the aftermarkets, way harder without a good base cal to start with.
How you like my post count Dustin?
Mark
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Dustin,Mark,and Eddie-thanks for your input and info. Now that you mention it-slew-I remember Tyler being able to make adjustments on the fly during past tuning sessions and if they worked we cycled the key and locked them in,Smitty
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There's thousands of other ways to make it better but you have to get far deeper into the software. Without being able to program on the fly, trial and error takes forever.
Dustin
That is one big downfall of mefi burn also no slew I use that alot. MEFI is not fast or dfi, the full mefi hud software
has way more adjustment than the aftermarkets, way harder without a good base cal to start with.
How you like my post count Dustin?
Mark
Dustin
That is one big downfall of mefi burn also no slew I use that alot. MEFI is not fast or dfi, the full mefi hud software
has way more adjustment than the aftermarkets, way harder without a good base cal to start with.
How you like my post count Dustin?
Mark
Can't believe your up to 38 post, you've been on fire. I think you need to go back and finish your apple sauce patent!
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delphi made a special mefi 1 that you could slew we still have one. You would use that ecm for dyno testing then save that cal and load into production ecm, that is what the check box enable dyno mode was for.You could also do screen shots with the engine running, mefi2 and on can do all that. Smitty, the dyno is the place to do most of the maping because if your dyno is able you can hold the eng very steady at all the break points, and control your temps up and down so you can make those corrections.
there are reasons why the tune changes from the dyno to the boat and the tuner has to know how and why it changes on his own dyno so he can make the right changes to his cal. A well thought out dyno cell is paramount to tune a efi engine properly.
there are reasons why the tune changes from the dyno to the boat and the tuner has to know how and why it changes on his own dyno so he can make the right changes to his cal. A well thought out dyno cell is paramount to tune a efi engine properly.
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Have you asked Bob at http://www.obd2allinone.com/sc/detai...fi&track=mefbn
He has been a great help to Ben & I in fixing what Crockett f*cked all up.
He has been a great help to Ben & I in fixing what Crockett f*cked all up.
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Have you asked Bob at http://www.obd2allinone.com/sc/detai...fi&track=mefbn
He has been a great help to Ben & I in fixing what Crockett f*cked all up.
He has been a great help to Ben & I in fixing what Crockett f*cked all up.
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Smitty, the dyno is the place to do most of the maping because if your dyno is able you can hold the eng very steady at all the break points, and control your temps up and down so you can make those corrections.
there are reasons why the tune changes from the dyno to the boat and the tuner has to know how and why it changes on his own dyno so he can make the right changes to his cal. A well thought out dyno cell is paramount to tune a efi engine properly.[/QUOTE]
When my motor was dynoed (july of 07) I spent alot of time on the dyno. I converted the motor from mefi3 to mefi4 and did a N/A tune with blower unhooked and a 1 bar map sensor and did a blown tune with a second ecm with 3 different boost levels/pulleys. Tyler Crockett spent alot of time tuning it on the dyno and we did make numerous partially loaded pulls so that boat would be much closer to a correct set-up when driven. For the most part when I finally did run the boat with my Rinda O2 tester the afr's weren't real far off in very many areas,the ones that were ,were rich in the mid to hi 10's around 2500-2900 rpm's and a couple of lean spots around 1800 but I rarely drove there. I re-tuned it from Idle to past 5000 because I want it correct and can't stand just wasting gas/washing the cylinders for no reason. The last thing I need to tune out of this set-up is the stumble it has between 900-1200 rpm's,I'm going to work on that this fri morn with the advice from you guys. On the dyno you could stab the gas off idle and it lit right up. After I get the blown tune where I want it I'm going to switch back to my N/A set-up for a couple of rides and go thru and fine tune that,Smitty
there are reasons why the tune changes from the dyno to the boat and the tuner has to know how and why it changes on his own dyno so he can make the right changes to his cal. A well thought out dyno cell is paramount to tune a efi engine properly.[/QUOTE]
When my motor was dynoed (july of 07) I spent alot of time on the dyno. I converted the motor from mefi3 to mefi4 and did a N/A tune with blower unhooked and a 1 bar map sensor and did a blown tune with a second ecm with 3 different boost levels/pulleys. Tyler Crockett spent alot of time tuning it on the dyno and we did make numerous partially loaded pulls so that boat would be much closer to a correct set-up when driven. For the most part when I finally did run the boat with my Rinda O2 tester the afr's weren't real far off in very many areas,the ones that were ,were rich in the mid to hi 10's around 2500-2900 rpm's and a couple of lean spots around 1800 but I rarely drove there. I re-tuned it from Idle to past 5000 because I want it correct and can't stand just wasting gas/washing the cylinders for no reason. The last thing I need to tune out of this set-up is the stumble it has between 900-1200 rpm's,I'm going to work on that this fri morn with the advice from you guys. On the dyno you could stab the gas off idle and it lit right up. After I get the blown tune where I want it I'm going to switch back to my N/A set-up for a couple of rides and go thru and fine tune that,Smitty
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Have you asked Bob at http://www.obd2allinone.com/sc/detai...fi&track=mefbn
He has been a great help to Ben & I in fixing what Crockett f*cked all up.
He has been a great help to Ben & I in fixing what Crockett f*cked all up.
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Hi Smitty, I was out on the water Friday, leave a message or shoot me an email and I get back to people pretty quick usually.
I suggest taking logs of runs as you are doing them, and then you can stop and scroll back through them. As you hone in on things, watch your knock retard values closely and alter your spark and fuel values accordingly, especially as you are getting into heavy boost.
You can upload your changes on the fly and watch how the engine responds. I find a little quiet time between runs, and looking at things in the 3D graphical view to see how smooth your maps are staying is the easiest for most people. It takes some experience to be inputting values on the keyboard and burning to the controller when you are moving fast and the boat is bouncing around. Trying to watch your wideband, with bright sun and rough water doesn't make it any easier. With a little time and patience, you'll get great results.
I suggest taking logs of runs as you are doing them, and then you can stop and scroll back through them. As you hone in on things, watch your knock retard values closely and alter your spark and fuel values accordingly, especially as you are getting into heavy boost.
You can upload your changes on the fly and watch how the engine responds. I find a little quiet time between runs, and looking at things in the 3D graphical view to see how smooth your maps are staying is the easiest for most people. It takes some experience to be inputting values on the keyboard and burning to the controller when you are moving fast and the boat is bouncing around. Trying to watch your wideband, with bright sun and rough water doesn't make it any easier. With a little time and patience, you'll get great results.