Guest Matthew123 Posted July 10, 2007 Share Posted July 10, 2007 I would like some help on setting up my AFR target tables. I'm not sure how to do it. My current setup is 280 zxt stock turbo injectors MSA stage 2 turbo cam stock turbo @ 6 psi n47 head with dished pistons If more info is required i will post it. Thanks Quote Link to comment Share on other sites More sharing options...
gearheadstik Posted July 10, 2007 Share Posted July 10, 2007 I'll will tell you what I've been told, but I'm in the same boat so others will have to put in input too....I'm just going by what buddys speeder and olie05 have shared w me. I agree with Rick when he says 13.8 seems to be a good ratio to idle on a L28ET, leaner kinda breaks up some. 15 under light cruise loads can make you get up to 30mpg or so on the road . 12.5 is a good full throttle but no boost. 11.5 under boost should keep you safe if timing is right "that was one of my first problems". You should have a smooth transition between these values even though I have not figured that one out yet. All credit on this goes to my buddy speeder, It seems to be doing great for me and I'm sure you could push the limits more but I would'nt on set up. I used the VE analyzer to generate the majority of my table, If you have not used it, go slow cause if it jumped into a load higher than you've been it may shoot lean or rich if your numbers are not about right....I changed mine to be near the numbers that I had achieved as I went getting on it harder and faster as I went. I may be wrong on this and someone please correct me If I am, cause I would love to know how if I'm wrong, But I think the VE analyzer will only go up to 150kpa so I guess you and the dattalogger are on your own after that? Good luck and God speed Quote Link to comment Share on other sites More sharing options...
gearheadstik Posted July 10, 2007 Share Posted July 10, 2007 P.S. If you know read this and know any other good threads on these topics please share. I'm in the same boat on learning the system too and sometimes have a hard time under standing the megasquirt sites lingo. Thanks Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted July 10, 2007 Share Posted July 10, 2007 my fuel map screen had kpa on 1 axis-my brain doesnt work in kpa so i looked up a conversion formula to convert kpa to vacuem/boost in/hg -psi si i could better understand what i was doing.after that i plugged in my values in my a/f table and turned on the auto tune function-but you need to have your ms wired into a wideband o2 for that.that made the car driveable-i drove it this way for a few monthes but it is not perfect .i damaged some pistons on high boost this way.after building new bottem end i have been working on data logging-.i run a very old laptop with a floppy disc in the car and pull the floppy and download it into megalogviewer program.this program will correct your fuel map.it takes a 20 minute+ log and reworks the fuel map.problem is somewhere i read that you should do this with the autotune turned off-so i need to turn off auto turn and drive again and rerun that log into megalogviewer to see what comes out.i have an old desktop computor on a cart to wheel up to my car -the 17" monitor is easier on my old eyes.some people just look at the datlogs-my come out in excel -and correct the fuel map and test drive again.but the traffiic is too bad and i can only run hard at night.when you drive your car if you take a note of what vacuem readings you get at different rpm ranges you can guess on the af table enough to get the car useable-just be easy on boost.you have to run the car-datalog- adjust fuel map-drive again with a little more boost & log -adjust again.a 14/1 to 15/1 af at freeway speeds will get you very good mpg.i am seeing 25 to 26 at 70 to 80 mph.problem is my datlogging found that i am at 92% duty cycle with 15psi boost and 42lb injectors-time for more money.but calculated hp is at 400.figuring this stuff out took me some time because i am not a computor geek-and i am slightly hobbled by being to cheap to get a good laptop and i dont like working on a laptop. Quote Link to comment Share on other sites More sharing options...
gearheadstik Posted July 10, 2007 Share Posted July 10, 2007 How did you change that kpa? I am using ms and spark extra... I think you are using a different version.. Can I change kpa to boost in that screen? Quote Link to comment Share on other sites More sharing options...
mobythevan Posted July 10, 2007 Share Posted July 10, 2007 Remember to setup up you r correction values also, once you have the target AFR table created. You really want to set up the valuse that tell MS how much correction it can do in total, how much per step and how often between corrections. Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted July 11, 2007 Share Posted July 11, 2007 i wrote my kpa numbers from the fuel map down on a piece of paper and converted them with a formula i found on a metric conversion site on the net-there are probably ways to change this on the ms screen but i dont like to play with this too much-it would take to much time to fix a screw up. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted July 11, 2007 Share Posted July 11, 2007 I must be thinking of autotune for setting the correction values and steps, etc. You should use autotune first to get the correct VE table for the AFRs you want, then run with target AFR tables turned on. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted July 11, 2007 Share Posted July 11, 2007 OK, to change the authority and step sizes and correction amount, etc You go under the basic settings tab then go under exhaust gas settings. You will have to do some research, but it was my belief that these settings are used to make changes in the fuel to reach your target AFR values. Obviously you want your VE table as close to the desired AFR as possible so the least amount of corrections are needed to reach the target AFRs from the target table. I could be wrong about this, I haven't looked into it lately. Quote Link to comment Share on other sites More sharing options...
datman Posted July 11, 2007 Share Posted July 11, 2007 Just divide KPA value by 6.89..... 101.325kpa (atm pressure) / 6.89 = 14.7psi Quote Link to comment Share on other sites More sharing options...
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