mefi tuning question for experts
#22
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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
Most dynos will not load a engine with alot of power off idle like that. We have control over the water in and out of our break, from years of on water testing we know what kind of load is needed and our break can reproduce it. You could have tuned with your 2bar map on your n/a set up, call me and I will tell you how we do it. to much typing for me and if spell a word wrong or have bad gramer some keyboard comando will jump me. Remember I am from Louisiana lucky I can type at all. You did a great job with your set up keep at it you will be happy when your done.
Mark
Most dynos will not load a engine with alot of power off idle like that. We have control over the water in and out of our break, from years of on water testing we know what kind of load is needed and our break can reproduce it. You could have tuned with your 2bar map on your n/a set up, call me and I will tell you how we do it. to much typing for me and if spell a word wrong or have bad gramer some keyboard comando will jump me. Remember I am from Louisiana lucky I can type at all. You did a great job with your set up keep at it you will be happy when your done.
Mark
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Keep the Tunerpro and MEFIburn screens up at the same time. As you make changes in the bin in Tunerpro and save them, you can do uploads to the controller of that saved bin with MEFIburn. It takes about 10 to 15 seconds to do the upload with a MEFI 4.
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can you do that with the eng running?
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I'm digging this mefiburn program,I'm going to go out fri again and run my next smaller blower pulley and a 32 pitch prop. If the part throttle cruising afr's change much from where they are at I'm going to save a copy of the tune I have with my 4.0 pulley and the 30" prop and make the neccesary changes and create a second tune file that I can switch to with the laptop when I want to run that set-up. You could never do this with a set program without the ability to program your own tunes and upload/download them so I think thats cool. I'm going to work on the off idle too, thanks everyone,Smitty
Last edited by articfriends; 08-07-2008 at 12:46 AM.
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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.
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This is very interesting and while I have learned a few things reading this it is still way over my head.
Interesting that there are programs out there like these but I for one simply to not have the time, enough knowledge or the desire to risk my motors while experimenting.
I for one think that putting the motors on a dyno with a proven builder like Mark or Tyler that have years of real world experience is the smart way to go. Then you simply go boating and enjoy!
Interesting that there are programs out there like these but I for one simply to not have the time, enough knowledge or the desire to risk my motors while experimenting.
I for one think that putting the motors on a dyno with a proven builder like Mark or Tyler that have years of real world experience is the smart way to go. Then you simply go boating and enjoy!
![Big Grin](/forums/images/smilies/biggrin.gif)
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Interesting that there are programs out there like these but I for one simply to not have the time, enough knowledge or the desire to risk my motors while experimenting.
I for one think that putting the motors on a dyno with a proven builder like Mark or Tyler that have years of real world experience is the smart way to go. Then you simply go boating and enjoy!![Big Grin](/forums/images/smilies/biggrin.gif)
I for one think that putting the motors on a dyno with a proven builder like Mark or Tyler that have years of real world experience is the smart way to go. Then you simply go boating and enjoy!
![Big Grin](/forums/images/smilies/biggrin.gif)
You would be surprised how different an engine can run from being on a dyno to the final installation in the boat. I've seen some that came off the dyno and the tune is near perfect in the boat. Others you look at the tune in the boat and you wonder if it is the same engine you ran on the dyno just days before. Exhaust, fueling, cooling, accessories, and environment all play into it.
Ultimately what really matters is how it is tuned and runs in the final installation. In my opinion you are experimenting more by taking a engine straight from the dyno and running it and not tuning it in the boat or car. The real world conditions can sometimes be a very harsh critic.
Bob
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You would be surprised how different an engine can run from being on a dyno to the final installation in the boat. I've seen some that came off the dyno and the tune is near perfect in the boat. Others you look at the tune in the boat and you wonder if it is the same engine you ran on the dyno just days before. Exhaust, fueling, cooling, accessories, and environment all play into it.
Ultimately what really matters is how it is tuned and runs in the final installation. In my opinion you are experimenting more by taking a engine straight from the dyno and running it and not tuning it in the boat or car. The real world conditions can sometimes be a very harsh critic.
Bob
Ultimately what really matters is how it is tuned and runs in the final installation. In my opinion you are experimenting more by taking a engine straight from the dyno and running it and not tuning it in the boat or car. The real world conditions can sometimes be a very harsh critic.
Bob
Artic is doing right with different pulley's and props, that is key to making it right for all future envoirments. We go a step further, were lucky, we have our local lake at 800feet, then we go up to 6000 feet within 1 hour, but we only do this on new cals, get our multiplier tables right, make a few changes to the base table that we know won't effect much at sea level and then we go back to 800 feet, finish it off. From there, we now have a predictable cal for almost all envoirments. You also need to get up super early and finish the "cold start" area's, which I believe are some of the hardest to do. This is one major advantage to the dyno, you can turn that AC on and use water through the engine to get it cold, but once you start it at the lake, you only had that 1 shot.
Dustin